Why does Doxie seem frozen?

If Doxie is entirely non-responsive and won't turn off, insert a paper clip in the small hole on the bottom. No scans will be lost.

This is admittedly rare, and often indicates a defective SD card or USB flash drive.

Note that inserting a paper clip doesn't do anything more than force the scanner to turn off. It isn't a solution to any other issue you might be experiencing.