TRY this method to bypass the following Error: '"Unable to find Ubisoft Game Launcher, Please re-install Assassin's Creed II. Ubisoft Game Launcher: Error code 1."
Which version of game do you all have, Retail DVD or STEAM ?
First you need to Manually delete the entire 'Ubisoft Game Launcher' folder, e.g. from C:\Program Files\Ubisoft\Ubisoft Game Launcher. Also remove it from Control Panel----> Add/Remove programs (Programs & Features).
After that again reinstall the Game Launcher from the disk/DVD. Browse the DVD, and go to 'Support-----> Game Launcher', and run the UbisoftGameLauncherInstaller.exe file. OR, reinstall the software from here:
http://static3.cdn.ubi.com/orb...auncherInstaller.exe
Also give this a read, if using a STEAM copy of AC2:
http://forums.steampowered.com...thread.php?t=1179965
If the above methods still don't work, then you can try deleting the 'Registry' entries of the Launcher.