Support Code:300 The printer does not respond

In the last 2 weeks I'm suddenly getting a frequent error message on my MacBook Pro when I try to print to my Canon MX860 printer which I connect to over my WiFi network. This combination has worked flawlessly for several years, but now it suddenly keeps coming up with this "Support Code: 300" error.

I have deleted the printer several times and reinstalled. It will work for 12 hours or less and then I start getting the Support Code: 300 error again.

My notebook PC, sitting right beside my MacBook Pro, continues to print to this same printer with no issue.

Any suggestions?