If your MIDI interface and printer share the same serial port (printer port or serial expansion port), this problem can occur. To overcome this error message, you'll need to temporarily disable FreeMIDI from the serial port. Here's what you do:

1. While your Quickscribe window is open, launch FreeMIDI.
2. From the MIDI menu choose interface settings.
3. Click down the list for interface settings and choose "Not in Use" for the FreeMIDI port (if you're using FreeMIDI 1.36 or earlier, click the radio button for "Not in Use").
4. Go back to Quickscribe and choose Print window from the file menu.
5. When finished, go back to FreeMIDI and re-select 1MHz/32x on the FreeMIDI port (or Fast 2x for an interface set to fast mode).