The Appropriate Paper Size, LTR, is not available.

Hello,

I have a Canon ImageRunner Advance C5535i in my office.  Literally every time anyone sends a print job to the printer, we get an error that "The appropriate paper size, LTR, is not available.  Select another paper size, then press [OK] to start printing.  We have 2 trays full of standard 8.5"x11" letter paper.  We have to press OK for every single job.  Anyone have a solution to this problem?  It is very frustrating.