May be 1st disk wasn't installed properly. Try to cancel the installation, clean all installed data and install again from scratch.
It also could be the disk is corrupt... In that case you should ask your retailer for replacement.
Another possible solution - activate your key on Uplay and download the game from them. Though I'm not sure it will work with retail hard copy... So you have to be absolutely sure that it will work before even trying to activate your key on Uplay, since Uplay activation is very difficult to revert!
The code from retail copy will work if you want to download the game in steed installing from disk.Originally Posted by akunamatataa Go to original post
It might take loot longer to download and install the game depend on you internet connection .
But at least you get all files installed on your PC , in case like op might have corrupted disk .