Hi Tony and Noel,

Thanks for all your help, but none of that worked for me.

Using the File Utility functions, BIAB recognised that the associations had been removed, but Explorer didn't. Whatever I did in both the 32bit and 64bit apps (removing and adding associations), running both as Admin, Explorer still opened every SGU file in BIAB 32bit.

Even after removing the associations, Explorer still showed them as existing and the files opened just fine. Shutting down Explorer and opening it up didn't make a difference.

Cheers, Paul