Installed hotfix for error 3241 when you run RESTORE FILELISTONLY statement in SQL Server 2008 R2. But still get same errormessage.

Cumulative Update 13 for SQL Server 2008 R2 SP1.

I have installed this hotfix, now running 10.50.2876.0

But I still get the same error when trying to restore a backup.

What else do I need to do?