Downgrade Enemy Unknown to Patch 4 (356266) R&D

[Drakous79]

Welcome back! :)

 

Would be enough to diff patch 4 executable against the latest one? It is possible, there was some compatibility patch nobody noticed.

[Dethraker]

I remember not too long ago there being an update to the .exe for some reason, we didn't look into it too much but it did cause some mods we were playing around with on EU to no longer work. After discussing it briefly AzXeus got the feeling that EU is no longer moddable after the patch. If this is true then the only way to play EU mods would be with a backed up .exe and all the old files, phone home off, and Steam in offline mode. Best of luck though on figuring it out.

[Bertilsson]

Welcome back! :smile:

 

Would be enough to diff patch 4 executable against the latest one? It is possible, there was some compatibility patch nobody noticed.

Thanks.

 

Maybe...

 

After a little digging around I found a backup of the patch 6 version I used to create the downgrade mod (missing the EW folder).

 

When comparing that folder with the latest version I can see that only XComGame.exe has been changed outside EW folder.

 

If I install the latest version and use the downgrade mod to make it patch 4 version and manually replace XComGame.exe it should in theory work, but instead what happens is that I end up in the launcher and when selecting the to play EU it starts as a background process and nothing happens.

 

Most likely the problem is in \common\XCom-Enemy-Unknown\XEW\Binaries\Win32\XCOMLauncher.exe which was never included in the downgrade mod.

 

With some luck it would be enough to replace also that file with an older version and if it works it would be very simple to make the mod working again. But I don't think I have any backup of it to test the theory :(

[Drakous79]

Dethraker, if only XComGame.exe has changed, EU patch 6 mods should be working.

 

Bertilsson, you can rename the file to XCOMLauncher.exec. If there is no launcher, Enemy Unknown is always started.

 

Can you try to set XComGame.exe compatibility to Windows 7, please?

 

Also there is a post by Dubious about Windows 10 using DirectX 12 and XCOM expecting DirectX 9 files.

Edited September 9, 2017 by Drakous79

[Bertilsson]

 

Bertilsson, you can rename the file to XCOMLauncher.exec. If there is no launcher, Enemy Unknown is always started.

 

Can you try to set XComGame.exe compatibility to Windows 7, please?

 

Also there is a post by Dubious about Windows 10 using DirectX 12 and XCOM expecting DirectX 9 files.

 

I've tested pretty much every thing I can think of without any success.

 

Fresh install of P7 starts without any issues. If I replace XComGame.exe with P6 backup the game won't start. As long as I can't get past that trying to downgrade further seems pointless.

 

I have tried both Dubious DirectX advice and lots of compatibility settings as well as getting rid of the XComLauncher, removing EW DLC. When trying out different compatibilty settings the only effect I was able to get was to have the Steam bootstraper service go nuts and constantly restarting itself until I killed Steam.

 

One thing I have not tested (and is not very eager to do) is to install steam in the exact same directory structure as I had 2013 (today I have Steam\ as a root folder on C:\, in the past I had it inside another folder). I guess it is not impossible that hard coding file location inside the .exe is part of steams copy protection even if I do not think that is the case.

[dubiousintent]

Hello again, "unlikely one" :ohmy: . You been training with the "Spanish Inquisition"?

 

Steam now has instructions on moving their installs from the default "C:\Program Files\" folder tree, which is basically a reinstall. (See the "Installing Games on Vista+" article in my signature.) However, no one has accused them of consistency yet, so it is always possible they have some path requirement for XCOM:EU they don't for other games. Certainly didn't expect a stealth change to P6. Has anyone tried to figure out the ~500 byte change?

 

-Dubious-

[Bertilsson]

Hello again, "unlikely one" :ohmy: . You been training with the "Spanish Inquisition"?

 

Steam now has instructions on moving their installs from the default "C:\Program Files\" folder tree, which is basically a reinstall. (See the "Installing Games on Vista+" article in my signature.) However, no one has accused them of consistency yet, so it is always possible they have some path requirement for XCOM:EU they don't for other games. Certainly didn't expect a stealth change to P6. Has anyone tried to figure out the ~500 byte change?

 

-Dubious-

Yes, no one expects it! :P

 

From a quick file compare in HxD I can see that there are some differences in the first 250 bytes. After that the files are identical up until around 75%. After that point all bytes are different (or more likely offset) so something was obviously modified there. Jumping to the end of the file I also noticed that P7 has unique references to DigiCert and P6 has unique references to VeriSign.

[Drakous79]

Finaly at home so I can join the hunt :smile: The laptop spent few hours updating Windows 10, because it is used as a paperweight.

 

I installed Steam (C:\Steam) and copied a backup of EU P6 EW P3 to the computer. Steam downloaded around 200 MB of data (like DirectX) and new XComGame.exe. The executable has version 1.0.0.4963 = Enemy Unknown patch 6 (Patches on Nexus Wiki). File size seems to be inconsistent. I verified integrity of game cache out of curiosity.

 

XComGame.exe P6 I have access to:

• Win 7 - size 28 428 952 kB - version 1.0.0.4963 (the backup)
• Win 7 - size 28 428 568 kB - version 1.0.0.4963 (dev computer)
• Win 8.1 - size 28 428 584 kB - version 1.0.0.4963 (travel computer)
• Win 10 - size 28 428 584 kB - version 1.0.0.4963 (Steam 9-2017)
• Win 10 - size 28 428 584 kB - version 1.0.0.4963 (Steam 9-2017 verified)

 

Next I set Steam to offline mode and tried Win 7 and Win 8.1 executable under Win 10:

• Win 10 (Steam 9-2017 verified) - all ok
• Win 7 (the backup) - background process, no game
• Win 8.1 (travel computer) - background process, no game

 

The game starts (set -log switch), but doesn't work. Win 8.1 and Win 10 executables have the same size but different content. No compatibility settings work.

 

Next I tried Win 7 and Win 10 executable under Win 8.1 - background process, no game.

 

It seems that every version of Windows needs certain exe. We may be out of luck, because there were no Windows 10 back in 2013. The worst scenario would be to run downgraded XCOM on virtual machine with Windows 7.

Edited September 10, 2017 by Drakous79

[dubiousintent]

...

Jumping to the end of the file I also noticed that P7 has unique references to DigiCert and P6 has unique references to VeriSign.

Ouch! That explains it. Valve switched their security certificate provider from "Verisign" to "DigiCert".

 

When you go "offline mode", Steam says it is copying your "credentials" from the server to your local drive. When you launch the Steam Client in "offline mode", apparently it checks your locally cached credentials for a valid security certificate to compare against the certificate in the game executable. In the case of the "downgrade", it has the old certificate, so it fails the check and the Client refuses to launch the (to it) "pirate" game.

 

I think that officially makes the "downgrade" a "dead horse". You would have to hack P4 to use the "DigiCert" certificate, and that would constitute "piracy". Someone might ask Steam about it, but really doubt they would have any interest in that request, as they would have to purchase certificates from both providers to accommodate a few mod users. Simpler by far to tell them to just buy "EW".

 

-Dubious-

Edited September 10, 2017 by dubiousintent

[Drakous79]

I agree with you Dubious. If I run EU P4 backup on my Win 7 machine with the latest Steam (built Sep 6 2017, api v017) - background process, no game.