Ok it not just local then.
I covered for a guy in tech support last week.
And I got calls from around the US with this very same problem. It was not isolated to usb though. I had some guys with FC series graphtec with serial connections having the same issue. The major difference is these guys all run flexi. Cutmaster is a scanvec product too so i wonder if its the same issue.
A few guys were able to fix the problem by up grading to the latest free update (most often 7.0v1 to 7.6v2). A another fix is changing ports. If its serial, you can change the set up from COM1 to COM 2, 3, or 4. If its USB you can change it from USB001 on up.
Try that. post your results.
But overall it can't be isolated it must have some thing to do with a
windows update or a Norton ( or McAfee ) update. These two are the only two common things with the folks I've seen with this issue.