They will likely open. The question is what opening such an old file will look like--how it will translate. But since Finale will open a copy of the file, you should not lose the original unless you save the new version with the same name.

You don't indicate Mac or PC. If Mac, make sure that the .mus extension is visible (if not, check the file in GetInfo). Sometimes, the old Palatino font will not display all characters correctly including clefs. Usually, changing the default to Maestro fixes this.

Thank you for your replies. The old files are on PC but I'd like to move them to a new Mac. I no longer have the old PrintMusic installation CDs to install on my new Mac but am hoping to transfer all my typed music files to the new version.

My font comments will probably apply. Newer Macs do not like the old PC version of Palatino. Maestro wasn't available in 2001 IIRC.

PC files will have the file type suffix visible. No worries there.