MP600 Printer is being treated as a removable disk drive.

[Dino3]

Kept getting pop up to insert a disk into Removable Drive J: After awhile I started ejecting the drive after receiving message. Took care of the problem; however, now have discovered that printer does not work until I turn it off and then on again. When I do this, Removable Drive J: is back and so are the messages.The printer is connected by USB. I've had it for several years. At that time I was on Windows 7, then went to Windows 8 with no problem, then went to Windows 10 some months ago (right after they started releasing it) with no problem. Everything was working just fine until about a month ago when I started receiving the popup to install a disk in the removable drive J: 

[JohnnyRow]

I had a similar problem on a different Canon printer.  After much trouble, I eventually fixed it.  It had to do with the printer having a slot for removable USB memory stick.  I changed the default drive assignment for the printer slot from L to P and problem solved.  I don't remember the exact details but it had to be a higher drive letter than some others.  I think it was it searches through the successive drive letters and gets upset when there is an empty drive.  There is some situation that makes it stop the drive search, maybe when it comes to the first non-assigned drive.  I just made my drive assignment near the end of the alphabet and it worked.

[Dino3]

Thank you JohnnyRow!! I will give that a try.

[Dino3 · Accepted solution]

After the note from JohnnyRow I decided to uninstall the printer software, reinstall and ensure I had latest driver since I originally got the printer under Windows 7, then went to 8, and now 10. After reinstall noted that the software still assigned to Drive J: and the notices to insert a disk into J: kept coming.  As JohnnyRow suggested I changed it to P: It's only been three days but yet have had the notice and I was getting the notice a couple dozen times a day, so am keeping my fingers crossed. Thanks again JohnnyRow!!!