I solved my problem on the MG5520 using Windows 8.1 stuck with the "used by another computer" error!
I noticed in my settings (computer settings - devices - printers) that there are two Canon printers listed - make sure you DO NOT select the printer that ends in "WS" when trying to print a document. EX: "Canon MG5500 series printer" vs "Canon MG5500 series printer WS".
If you have any print jobs pending in that queue for that printer ending with "WS", then you will need to cancel all pending print jobs under the "WS" labeled printer before it will allow any other print job to be performed.
Next, when you go to print a document, make sure you select the correct printer (without "WS" at the end).
This cleared up the "being used by another computer" error, and I didn't have to uninstall or reinstall any drivers or disable any wireless settings or use a USB cable!
I was so happy that I even took the stupid half hour to register an account with Canon so I could share my solution to this annoying problem. And now I know that I should inform my wife to not print anything on the wrong printer queue anymore!
I hope this saves someone from the frustration I felt.
Here is a more discriptive walkthrough for technologically challenged individuals:
*This first part s not actually necessary - it is just to show you that there are two DIFFERENT print queues
Step 1:
Get into your PC settings menu. If you don't know how to get there, then go to your Apps screen and use the Search feature by typing in "settings". The first thing to pop up should be PC Settings (click on that).
Next, you have to select "PC and Devices" to the left of the screen
Then you want to select "Devices" to the let of the screen
There you will see a list of devices installed on your computer, and you should see two Canon printers (one ending in WS). EX: "Canon MG5500 series printer" vs "Canon MG5500 series printer WS"
Step 2:
Log into each user profile on your computer and check the print queues to see who is trying to print on the "WS" printer queue.
You can see the print queue by clicking on the little triangle in the bottom right of your screen, then clicking on the little printer icon.
If there are pending print jobs, cancel ALL of them for each user account on your computer.
Step 3:
Once all print queues are clear, try printing a document and be sure to select the printer WITHOUT "WS" at the end of the name and it should work!
Good luck!
