Hello TeeKay,
I understand a paper mismatch error occurs when you attempt to print with your Color imageCLASS MF8580Cdw. The mismatch paper error usually means the paper that is loaded in the printer doesn't match the paper size setting on your computer. For clarification, do you mind answer a couple of questions about your situation?
(1) Does the error also occur when you make a copy after placing a document in the printer and selecting COPY and the BLACK or COLOR START?
(2) What is the actual size of the paper (e.g. 8 1/2" x 11", 8 1/4" x 11 3/4", etc.) that is loaded in your printer?
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