Trouble sharing Fin2012 files between two computers

[JerrTann]

I'm passing Finale 2012 files between two Win7 OS computers. Several weeks ago one of the computers stopped letting me open files from the other computer, telling me it "could not delete" the file I was trying to open. Why is this suddenly happening, and how can I fix it???
Jerre

[miker]

Not sure. Have you restarted the computer? Are they both running registered copies?

You might have to contact tech support on this one.

[JerrTann]

Thanks for the quick reply.
Yes, both installations are registered with Make Music [Finale]. I should have mentioned I can't open files written by F2010, F2011 or F2012. F2009 and earlier I can open. If I save an F2009 file in F2012 I then get the "can't delete" message and it doesn't open. Also, both computers no longer recognize my keyboard which is connected by USB port. Both computers are running F2012b. I haven't tried uninstalling Finale on the computers and installing F2012 out-of-the-box with no updates because it's such a hassle. This is my last-ditch attempt before I do that.
Jerre

[miker]

What versions are you running? Your signature shows 2010. If that's the case, you would not be able to open 2011 or 2012 files, unless they are in XML format.

[JerrTann]

Sorry, haven't updated my signature in some time.
I'm running F2012b on both computers. One computer has F2010, 2011 and 2012 installed, the other has only 2011 and 2012. Everything worked fine last year when I first installed F2012. The trouble started some time after I installed 2012a or 2012b, didn't notice which update caused the problem since I was mostly editing instrument parts on one computer and making MIDI files to run in other applications on the other.