Just picked this up in the steam sale and cannot get it working.
I've tried every GFWL uninstall/reinstall fix I can find instructions for. No matter what I do, DS refuses to sign into windows live for game saves. The game launches fine, I would just really like to be able to save.
I see that people claim they have this running with no problems whatsoever.
How???
edit: Solved. Here's what I did, as a combination of everyone's advice. Maybe it will help someone else out.
Step 1) Uninstall "Microsoft Games for Windows Marketplace" from Programs and Features
Step 2) Uninstall "Microsoft Games for Windows - LIVE Redistributable" from Programs and Features
Step 3) Reboot
Step 4) Download GFWL installer from here:
http://www.xbox.com/en-US/LIVE/PC/DownloadClient
Step 5) Right click the installer, compatibility tab, set to compatibility for Windows 7. Apply and OK
Step 6) Right click the installer, run as admin. Hit next until it's installed.
Step 7) GFWL should prompt you to download and install the Windows Live Sign In Assistant. It will link you to an .MSI file that did absolutely nothing on my system. Instead, download the .exe installer from here and use Windows 7 compatibility mode on it:
http://www.microsoft.com/en-us/download/details.aspx?id=26686
note: At this point all the advice says the game should now be working and sign into Live. It doesn't. It's still fucked. Keep reading.
Step 8) Either uninstall/reinstall Dark Souls, or verify cache through steam. This forces the Live redist to re-run for DS which will, I'm guessing, pick up the new GFWL/sign in assistant/whatever and start working.
Step 9) Run Dark Souls. GFWL doesn't need to be running or signed in prior. Once the game loads, the windows live sign in should drop down from the top and ask you to sign in (just like a game on an xbox would).
Hope that helps someone who was having the same troubles and rage I was. Lesson learned: never buying a GFWL game again.