If the "Cancel" button isn't working, it means the computer thinks the file is still being transferred. is the most reliable fix because it forces the computer to let go of the file so you can delete it.
10/10 for usefulness.
Troubleshooting: How to Clear a Stuck Print Queue We’ve all been there: you hit "Print," and then... nothing. You check the status, and there it is—a "stalled" or "error" message holding your printer hostage. Simply clicking "Cancel" doesn't always work, but these proven methods from Microsoft Support and Cartridge People will get your documents moving again. Method 1: The Quick Cancel (Start Here) how to clear print queue