Cygwin Time Machine Information

Cygwin Time Machine

Please Help! Go HERE to see if you might be able to help out the project!

NOTE: Please remember to use the '-X' option when running setup!! (See update 08/05/2008 for details).
Also note that you must run Setup from a command line in order to specify this option.

UPDATE: 02/01/2024: cygwin 3.5.0-1 release

I'm happy to announce update of the first Cygwin 3.5 release


- Cygwin 3.4.10 was the LAST major version supporting

  - Windows 7 / 8
  - Windows Server 2008 R2 / 2012

- Cygwin 3.5.0 runs on

  - Windows 8.1 / 10 / 11
  - Windows Server 2012 R2 / 2016 / 2019 / 2022
  - and (hopefully) all upcoming releases of Windows.


See here:

UPDATE: 01/17/2024: Upcoming desupport notice concerning Cygwin.

 We're planning to release Cygwin 3.5 end of this month (Jan 2024) if
 nothing serious crops up.


 One major change in this release is dropping Windows 7, Windows 8,
 Windows Server 2008 R2, and Windows Server 2012 from the list of
 supported operating systems.

 For those of you still running one of these old systems (despite
 them all being unsupported and unpatched by the vendor), we will
 keep the last 3.4 release (3.4.10) available for quite some time.


 The minimum supported OS version when running Cygwin 3.5 will be
 Windows 8.1 and Windows Server 2012 R2.

See here:

UPDATE: 12/04/2022: Upcoming desupport notice concerning Cygwin.

- Cygwin 3.4 is the FIRST major version dropping support for

  - 32 bit Windows including WOW64 on 64 bit Windows.
  - Windows Vista
  - Windows Server 2008

- Cygwin 3.4 is the LAST major version supporting

  - Windows 7
  - Windows Server 2008 R2
  - Windows 8
  - Windows Server 2012

- Cygwin 3.5, which will probably be release at some point in late 2023, will run on

  - Windows 8.1
  - Windows 10
  - Windows 11
  - Windows Server 2012 R2
  - Windows Server 2016
  - Windows Server 2019
  - Windows Server 2022

There are no plans to deprecate support for 64 bit systems starting with Windows 8.1 / Windows Server 2012 R2 any time soon.

See here:

UPDATE: 11/28/2022: Cygwin HAS drop support for 32-bit Windows! Yes, Cygwin is now 64-bit only!
See here:
Here is the circa URL for the last 32-bit release of Cygwin:
The last 32-bit version of Setup is 2.924. Copies of Setup can be found here:

OLD UPDATE: 10/29/2021: Cygwin is dropping support for Windows Vista & Windows Server 2008.
See here:
The last major version of Cygwin to support Windows Vista & Windows Server 2008 will be 3.3.X (currently 3.3.1-1).
NB: Cygwin is also dropping support for 32-bit Windows after this release.
That, like all other versions of Cygwin, can be found here at the Time Machine.
Here are the tentative circa URLs (these are not finalized yet):
These will be updated to eventually be the final circa.
The last tentative version of Setup to support Windows Vista & Windows Server 2008 is 2.909. Copies of Setup can be found here:
32-bit: setup-x86-2.909.exe
64-bit: setup-x86_64-2.909.exe

OLD UPDATE: 05/04/2020: The site has been restored. Please report any issues to me.

OLD UPDATE: 03/20/2020: The site suffered a non-recoverable disk failure (Thanks Amazon Web Services! :-() causing a complete loss of the archive. Fortunately, I have a complete copy, but it will take a few weeks to get it restored. Sorry for the inconvenience!

OLD UPDATE: 10/24/2017: Changes to Setup (v2.882) and setup.ini. As of v2.882, Setup supports having multiple "versions" of a given package, and the generation program that creates setup.ini will now be adding multiple [prev] and [test] sections for each package that has multiple versions tagged as such. As a result, older Setup versions may not work with this latest format change. People using the Time Machine will need to be a little bit sensitive to accessing circa after this date.

OLD UPDATE: 03/16/2017: The Cygwin Time Machine has moved! It's new home is the domain. Go there for details.
In a few weeks the old webserver will automatically re-direct you to the new site. Sadly, I can't do that for the FTP server, so you will have to mentally redirect yourself. :)

OLD UPDATE: 10/14/2016: A helpful user alerted me to a problem with the 64-bit circa of The Last Version Of Cygwin That Supports Windows XP. It's since been corrected. If you were trying to pull that circa and getting "bad" or missing packages, please pull the setup.{xz|bz2|ini} files again and try install again. You may need to delete the setup.* files from your local Download directory. Please report any problems you may still encounter there after.

OLD UPDATE: Cygwin has dropped support for Windows XP. See here:
The last version of Cygwin that supports Windows XP is 2.5.2-1. That, like all other versions of Cygwin, can be found here at the Time Machine.
Here are the circa URLs:

The last version of Setup to support XP is 2.874. Copies of Setup can be found here:
32-bit: setup-x86-2.874.exe
64-bit: setup-x86_64-2.874.exe

UPDATE: There have been some reports of the newer versions of Setup hanging on downloading large files (>23MB) when run on Windows XP. If you encounter such problems, please contact me and I'll supply you with an older Setup that may help alleviate this problem.

UPDATE: Cygwin is in it's v2.X lifetime now and the Setup program is now two programs: setup-x86.exe for 32-bit or setup-x86_64.exe for 64-bit. If you find the latest Setup is unable to access the Time Machine, please email me (see Contact below). I have an archive of many of the older versions of Setup that may work for you instead.

UPDATE: Cygwin has dropped support for Windows 2000 and Windows XP pre-SP3, as of version 1.7.19. The last version of Cygwin that supports Windows 2000 is 1.7.18. That, like all other versions of Cygwin, can be found here at the Time Machine. Here is the circa URL:

The corresponding version of Setup for this release is 2.774. Copies of Setup can be found here:
32-bit: setup-2.774.exe

OLD UPDATE: As of 3/23/2013, the Time Machine is now recording 64bit Cygwin! This is still in it's early dev stages, so be patient. Also, I don't have a reference for setup64.exe yet, so check the Cygwin website for now.

OLD UPDATE: As of 1/1/2010, Cygwin 1.7 is now the main branch for Cygwin. You should be using the latest setup program from the Cygwin main website. It can access any of the 1.7 or 1.5 releases (well, at least it should work :-). Cygwin also has a snapshot of the last 1.5 release (see the Cygwin Legacy note below for details if you wish to use the official last 1.5 release from the Cygwin website). You will need to use the special setup-legacy installer for that. Or, you can just use the latest setup and point it to the Time Machine which has the same snapshot available.

OLD UPDATE: As of 12/23/2009, Cygwin has taken that giant leap forward with it's next major revision: 1.7! It's now the default release for Cygwin!! The Time Machine contains all of the intermediate test circa snapshots (ie: "release-2") in case you want them. Additionally, there's a "legacy" release of Cygwin (1.5) being maintained (for the time being). The Time Machine also contains the circa snapshots of this as well and will continue to snapshot it. See here for some details.

OLD UPDATE: As of 08/05/2008, Cygwin has added a security signature as part of setup.ini (ie: setup.ini.sig). This is to satisfy a security vulnerability (CVE-2008-3323) discovered concerning setup's loading of setup.ini (a Man-in-the-Middle type of attach). You can read here for details.
The Time Machine does not currently archive this signature (but may in the future). So, in the mean time, when running setup.exe and downloading from the Time Machine, you will need to specify the '-X' option to disable the lookup of the signature.

OLD UPDATE: Cygwin is taking a giant leap forward with it's next major revision: 1.7! But it's still experimental as of yet. So, it's off in it's own special release area (release-2). In honor of this, the Time Machine is now archiving this special release area and providing circa snapshots. See here for some details.

OLD UPDATE: As of 4/21/2005, the Time Machine has be reformatted! What does this mean? Previously the circa of Cygwin was created based on the date & time I archived setup.ini. Since all archive revisions of setup.ini were linear and progressive in time and somewhat close to the actual release of that revision of setup.ini, this mostly worked. However, since I've been receiving older versions of setup.ini (Thank You to all who have contributed!) I no longer have a correlation between the timestamp within setup.ini and the date & time I archived it. So, something had to be done. I've changed the creation process so that now all circa are based on the actual setup-timestamp within each revision if setup.ini. What does that mean? Well, for starters, it gives it a direct correlation between the timestamp and the circa directory hierarchy. That's a good thing. However, since this nolonger has relation to the previously generated circas, the master index and all circa indexes are now different. That's a not-so-good thing. What's that mean? Well, if you previously found a timestamp in the master index and used the provided web link to get that circa of cygwin, well, the web link has now changed. However, in the interests of providing a consistent service, I've left, intact, the previous circa directory hierarchy for those who have already used the Time Machine.


"Dead Simple Instructions"

It's fairly simple to use the Time Machine. The Time Machine hyperlink (shown in the following instructions) is a series of Cygwin snapshots from many points in the past displayed in a table format. If you click on the Circa hyperlink, you'll see a list of the packages as they existed at that point in time. You will be able to search for your package using this Circa hyperlink (see the following numbered instructions).

If you have a partial package installation already and find you need other packages from that time period. Check the setup.ini that should be stored with the packages in your local download area. Near the top should be a 'setup-timestamp' entry. Find that number in the Time Machine table. Use the FTP hyperlink and you'll be able to grab the rest of the packages from that same snapshot.

If you don't find your timestamp in the list. Don't Panic! It's very possible that I do have the packages that make it up. Since each setup.ini is a snapshot in time, it's very possible that the Time Machine has collected all the packages before, during, and after that time frame, just not that specific setup.ini time stamp. Thus, all you need to do is send me the setup.ini. I'll check that I do have all packages from that point in time and I'll add it to the Time Machine, thus making it available to everyone. And, if I happen to be missing certain files, I'll probably ask if you happen to have a copy. Check out the current list of Holes in Time.

  1. When you run the Cygwin setup (e.g. if you have a desktop link to the setup program like sensible chimpanzees) be sure to use the "-X" option (i.e. add the "-X" option in the link) to the end of the command.
  2. Go to the time machine top-level snapshot index ( for the 64-bit version).
    You'll see a table of Cygwin versions, timestamps, Circa hyperlinks, and URL paths displayed. These represent the revisions of Cygwin as of the date shown.
  3. Browse through the table entries (you may click on the Circa link to see the contents) looking for the package you need. It is best to start near the last point in time you knew the package was available. Once you find the latest package, copy the hyperlink address (in the "Link" column) for the package to the clipboard.
    The URLs on the right side of the table are meant to be used as a package source path when you run setup.exe. For example. If you want the January 21st, 2005 at 9:20:32am "version", copy the hyperlink (from the "Link" column) shown in bold to the clipboard.
    Version Setup Circa Link
    Timestamp Version
    1.5.12-1 1106328032 2.457.2.1 2005/01/21-092032
  4. Run setup-x86.exe for 32-bit or setup-x86_64.exe for 64-bit. (Remember to use the "-X" command line option).
  5. When prompted for the package source location, paste in the URL from the clipboard and click the "ADD" button. Please remove any leading or trailing spaces when you paste it.
  6. Proceed with the installation as normal.
I hope you find this useful as the Time Machine is very useful when you have a new installation and want a package that is not in the latest release any more.

Cygwin Legacy (ie: 1.5)

Cygwin has moved to a new major release (1.7). With that, the older version (1.5) of Cygwin is now officially "put to pasture". However, the good folks at Cygwin do understand that many users may need to maintain the older versions in a production environment. To that end, they have setup a "legacy" repository of the older release (dubbed "Cygwin Legacy"). The Time Machine will, as it did for the test releases of 1.7, maintain circa snapshorts of this repository and offer it to those who might need it. After all, there's no guarantee the Cygwin folks will keep the old legacy repository around forever.

As before, there's a different setup program you need to get and run:
Archived version: setup-legacy.exe

In order to use it with the Time Machine, you need to point to the new circa release area. Go here "" and get the path link to the circa you want. Then, follow he same procedure you'd use for the regular Time Machine. It's that simple! No, really!

Cygwin 1.7 !!!

Cygwin has made its major leap forward to it's nextgen version: 1.7. It's ready for primetime! The Time Machine maintains circa snapshots of the test releases for 1.7, but, as before, you'll have to do something a little special to use them.

There's a different setup program you need to get and run:
Archived version: setup-1.7.exe

In order to use it with the Time Machine, you need to point to the special circa release area. Go here "" and get the path link to the circa you want. Then, follow the same procedure you'd use for the regular Time Machine. It's that simple! No, really!

Keep in mind that these are just the old test releases. If you want to use the main-stream 1.7 releases, the just get the latest installer from the main Cygwin site and point it to the Time Machine circa of your choice.

Cygwin Setup Archive

Again, against my better judgement, I have made available my archive of Setup versions. This, hopefully, will help people who are looking for a specific version of Setup.
Go here "" and click on the version of Setup you need.

Does Anybody Really Know What Time It Is?
(does anybody really care?)

DOCTORS WARNING: The Time Machine is in flux! Use at your own discretion, void where prohibited, no money back guarantee, your mileage will vary, do not induce vomiting if swallowed, and last (but not least) DO NOT TAUNT HAPPY-FUN BALL! (really, it's for your own good :).

Let me state that there is no formal support for older era Cygwin, and my offering this in no way implies any responsibility by the Cygwin community to support (or even condone) it as such. Cygwin is a constantly moving project and as such really only offers a "current" release of it's pacakges, which can and do change on a daily basis. The Time Machine is being offered out of gratitude to the Cygwin maintainers and contributors for their efforts in making Cygwin possible, and as a practical way for people to examine the project as it matures (a historical retrospective, if you will). There has been need in the past for people to install older era Cygwin. The reasons are numerous and often stem from needing to maintain older software dependent on older Cygwin or as a way to examine how some packages had evolved over time, possibly to extract some of that older code for scrutiny.

You may use this software knowing that there are bugs. If there weren't bugs, the project would be fairly static. But it's not. Did I mention it changes on a daily basis? Anyway, if you find a bug, or have a problem, you have three options:

  1. Live with it.

    This should be self-explanatory (hey, it's free after all!).

  2. Migrate to the next era of the software.

    This means you might be able to solve your problems with minimal change in software. This only works if your specific problem had been addressed at some point by the project. Finding that information is difficult but may be buried in the Cygwin email archives.

  3. Migrate to the current release of Cygwin.

    This is the prefered method as it means you will be using current Cygwin and stand a ghost of a chance of possibly getting it solved via the Cygwin email list and community. I understand that it's not always possible to take this option, but if you can, that will be the most expedient way of handling things.

Now, be that as it may, I will attempt to answer questions or problems (see Contact below) that people might have concerning installing older era Cygwin through the Time Machine.

Oh, and one other thing. Please do not annoy the good people of the Cygwin list with questions about ancient versions of Cygwin (like "B20"). It only makes them mean (well, meaner :). Seriously, the Cygwin community is focused on moving forward, not looking back.

Ups and Downs in Time

I should state here that using the Time Machine is not for the faint of heart. You can quite literally destroy your Cygwin environment, damage the Registry, make your lights blink on and off, cause massive power outages in your neighborhood and otherwise cause the total destruction of the earth! (Oh, wait... sorry ... been watching too much Doctor Who again :). But seriously, you can chowder your Cygwin environment if you are not careful.

If you have an existing Cygwin installation and feel the need to go back to a previous era of Cygwin, please consider carefully backing up your environment first. What I mean by this is saving anything you've changed with reguard to init files or /etc files. Why? Because I'm going to give you some practical advice: If you want to install a previous era of Cygwin, it's best to de-install everything first, delete everything under your Cygwin root directory and then install the chosen era of Cygwin. Why? Because this is the best possible option for giving you a clean environment with which to start from.

In theory you should simply be able to select the older version of any/all packages and the installer will remove the "new" packages first, then install the "old" ones. In practice it's not so cut and dried. As the packages are revised and improved, things move around and bits and pieces either get left behind or get renamed or checked for where previously they did not. It's best to simply clear the disk to ensure those left over bits don't break things. Another reason has to do with package dependencies. Over time packages might change their requirements of what they need to work properly. As newer packages become available, older packages may be renamed, or subsumed into other packages and thus the original package be retired. So, you could downgrade just one package and cause several other "retired" packages to be re-installed and possibly cause overlay and corruption of other "new" packages. The same is true upgrading from a truely vintage era (eg: "B20" or 1.3.10) to current time.

One last reason has to do with the progress of software development. A given package could provide a set of functionality early in life, then much later completely change that functionality requiring applications that use it to change as well. This is not only true of Cygwin, mind you, but of all software. Software is mostly about synergy; things working together in concert. Like an orchestra, get one horn blowing the wrong note and the whole symphony falls apart. To maintain the synergy of a given era of Cygwin, it's best to load everything cleanly.

Now, given the above, you can throw caution to the wind and upgrade (or downgrade) willy-nilly. Most people using the Time Machine will either simply be grabbing the rest of the packages from an era that matches what they already have, or be slowly, carefully, migrating through time to the next era up or down from their current point in time. This should mostly be safe, unless you are crossing a major Cygwin release boundary, say going from version 1.3.22-1 to version 1.7.1-1. That might not be so smooth.

So, please, for the sake of your hair and my sanity (as well as everyone else who uses Cygwin), play in a clean sandbox. You'll thank me later.

Back to the Future and Forwards Again!

!ALERT! Table updated as of 07/18/2006 !ALERT!

Here's how you can help the project. I'm always on the lookout for old setup.ini files (or packages I'm missing which are part of a given circa). These represent the snapshots of Cygwin. The Time Machine currently only goes reliably back to 03/11/2003 (setup-timestamp: 1047280802) though there are some circa stored from before then. Normal usage of Setup.exe means downloading the necessary packages into a "download directory". This directory will also contain the matching setup.ini file.
In your daily encounters with Cygwin, or people who might be using Cygwin, please spend a minute and look at the timestamps in the setup.ini in the download area. If the timestamp predates 1047280802 (ie: is a smaller number) then please request that a copy of that file be emailed to me (see Contact below). My mirror predates the Time Machine, and so it's possible that I could materialize even older circa of Cygwin if I only had the setup.ini to go with it. So, please, if you find an old dusty PC which hasn't been running in a while and you think it might have Cygwin on it, please give it a once over. Or if you have a buddy who hasn't upgraded his Cygwin in quite some time, please ask to examine his setup.ini. I thank you for your participation.

Holes In Time

From time to time the Time Machine breaks down (rather like a real Tardis, eh?). As a result, there are gaps in the chronology. This means some packages weren't copied or that a circa of setup.ini failed to be archived.
Below is a table containing the known gaps in Cygwin history that need to be filled. If you happen to have one of the missing files dated as such, please send me a copy. I thank you and those who use the Time Machine thank you!

(Current list of gaps in Time Machine chronology)

File Date Timestamp
Name From - To From - To
setup.ini (x86) 09/29/2014 - 10/05/2014 1412032244 - 1412500208
setup.ini (x86_64) 09/29/2014 - 10/05/2014 1412032244 - 1412500208
setup.ini 06/01/2013 - 06/04/2013 1369949427 - 1370373034
setup64.ini (64bit) 06/01/2013 - 06/04/2013 1369949427 - 1370373034
setup.ini 05/13/2006 - 07/14/2006 1147567204 - 1152906012
setup.ini epoch - 03/11/2003 epoch - 1047280802

"Download incomplete. Try again?"

You may encounter this warning from Setup pulling from the Time Machine. Let me explain. You see, on occasion a Cygwin package maintainer inadvertently (or sometimes overtly) uploads a different package under the same name & version. This can occur for many reasons, but usually falls into the category of "a mistake was made and people have been sacked". :) Ok, well, whatever the reason, it's often after the time that that specific circa of setup.ini was released and copied forth unto the mirrors and ultimately to the Time Machine. It's a flaw and not one I can correct for easily. But the upshot is that Setup complains about this difference of opinion. The package info in the setup.ini says one thing and reality says another. All in all it's better to have the "corrected" version of the package. Your options are:

  1. Deselect the package (this should have been done first, but oh well)
  2. Choose "No" when prompted and continue on
  3. Complain to me and I can send you an updated setup.ini with all the corrections in it (and fix it on the site for others)
  4. Choose a slightly newer circa and try again.

Sometimes a package will be missing. This is rare, but does happen. I can't really help with this. Your only hope is that someone else might have an old machine with that missing package. However, often these are the "_obsolete" or "_update-info-dir" or even "_autorebase" pseudo packages. I would suggest first trying the next circa up (or down) but if that doesn't help and it is one of these specific packages, they can largely be ignored as these are fixup and deletion packages run after the install is complete. I may be able to manufacture these as they are fairly mechanical and predictable. If you let me know which specific one is missing I might be able to manufacture it for you. No guarantees, though!

Cygwin Mirror

I maintain an unofficial mirror for the web site. Currently I sync from everyday in the early AM (PST).
Additionally, I have been keeping every version of all packages starting back on April of 2002 (or possibly November 2001 .. not sure about that ..). I've also been archiving all setup.ini, setup.hint and md5.sum files for all packages since March 2003. If you need a specific version of these files, I might be able to provide it to you. Why? Well, if you work for a company who wants to maintain a specific "version" of Cygwin, then keeping and using an older setup.ini, and the corrosponding packages, would really be useful. As for myself, I feel that change is good and the latest "version" of Cygwin is more likely to provide a better working environment and the latest fixes.
In setup, enter "" as a User URL in the "Choose a Download Site".
In setup64, enter "" as a User URL in the "Choose a Download Site".

My Thanks

Thanks to Brian S. Wilson for the "Dead Simple Instructions" to using the Time Machine. Hopefully they help first-time users make things work, trouble free. If Brian! :-D


If you find something wrong, either with the website, accessing the files on the webpage, or with the actual packages or content themselves, please contact me (Peter Castro) at:

Last Updated: 02/01/2024