My problem was when I launched the game, it would get to the point where it was about to start the first mission "The Cousins Bellic" and then the game would crash.

To fix this, first uninstall any Games For Windows Live programs you may have installed.

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Once that's done, download and install Windows Live Sign-In Assistant [NOT 6.5]
Download here: https://www.microsoft.com/en-us/download/details.aspx?id=26686

Then, download and install Games For Windows Live. Even though we have Windows 10, click the download for Windows 8.
Link here: https://support.xbox.com/en-US/games/game-setup/games-for-windows-live-info

Now, download and install Windows Essentials 2012
Link: http://download.cnet.com/Windows-Live-Essentials-2012/3000-20418_4-10805747.html

At this point, we have everything we need. Try to sign in to Windows Live Messenger. It will fail, but this is neccessary.

Hold the Windows key and R at the same time on your keyboard. In the window that opens, type "regsvr32 softpub.dll" without the quotes.

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After you've completed all the above, now its time to run the game.

Once it comes to the main menu, hit the Home key on your keyboard and sign in to Games For Windows Live.
It will probably tell you it needs to upgrade, do that, then it will tell you to close the game to finish the install. Do it.

Once its done, run the game again, hit the Home key, and sign in once more. This time it should work.

Once youre signed in, go ahead and start a new game and it should start right up.


Let me know in the comments if this worked for you.