There's no database changes from 7.1 to 7.5 for access that i know of, on ms sql i believe there's a couple new stored procedures....
I looked at line 300 on the common.asp and it's requesting the Upload_avatar field on tblConfiguration, that tells me that you're trying to upgrade from a beta version (not 7.1 as you stated) as that field was not added until v7 final or one of the latest betas.
So the only thing you can do is look at the version history and make the database changes manually.
If you're really upgrading from 7.1 then either your database got corrupted (i don't think so cuz you would also get errors with 7.1) or when you upgraded from a beta version you had the same problem and instead of adding the field to the database you just commented that line on your common.asp. If you don't use the avatar upload feature then you should be able to just comment out line 300 but you might then get other errors as other changes might be needed on the database.