“Failed zlib call. Please reboot, verify the game data, or reinstall the game. For more information, please visit: http://rsg.ms/verify”

While using an old HP ProDesk 400 G3 MT with Windows 11 installed on it (and I was surprised it was actually running this version of Windows), I installed GTA 5 on it after waiting a long 4-5 hours for it to install, I was finally playing the game. Of course I had installed a better video card and upgraded the CPU in this machine in order to achieve this much greater performance. While playing that exact game, I came across this really annoying error code… see below.

What is recommended on the Rockstar Games support website is to uninstall the Rockstar Games Launcher, then reinstall it. You should also delete the following folders:

• C:\Users\[username]\Documents\Rockstar Games\Social Club

• C:\Users\[username]\Documents\Rockstar Games\Launcher

• C:\Program Files\Rockstar Games\Launcher

• C:\Program Files\Rockstar Games\Social Club

• C:\Program Files (x86)\Rockstar Games\Social Club

After that is done, you should restart your computer. Now, reinstall the launcher either by downloading it from this link or by clicking on the installer saved in your Downloads folder. During the time that you are installing the Rockstar Games Launcher, be sure to tell it to scan your computer for previously installed games, and it should find GTA 5 in there after the scan is finished.

The only problem with this solution provided by Rockstar Games is that it did not fix the problem for me, I kept trying to go back to launch the game and actually play the game for a bit, then I would just get a different error message. My guess is that this old HP is just too old for Windows 11 and should maybe be downgraded to Windows 10 then have GTA 5 be reinstalled, to then see if you see any more errors.

I have not tried this yet but I will let you guys know how it goes. Another tip to try is to launch GTA 5 directly from the icon on the desktop without launching Social Club first, this might also make a difference. If you know of other solutions to this error message please leave a comment down below, thanks.