On the covered Brother printer, Size Mismatch, Size Error DX, Wrong Paper Size means the paper in the tray is not the correct size — Brother's own wording for Size Mismatch. Brother uses Size Error DX for the two-sided case, where the size set in the printer driver is not one the machine can duplex; inkjet models word the same condition as Wrong Paper Size. First, compare tray guides, paper and print settings.
Try in this order
0 of 2 completedWhat to do first
ReversibleCompare tray guides, paper and print settings.
Correct only the documented fault domain
ReversibleMake all three use the same supported size.
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What does Size Mismatch, Size Error DX, Wrong Paper Size mean on a Brother printer?+
the paper in the tray is not the correct size — Brother's own wording for Size Mismatch. Brother uses Size Error DX for the two-sided case, where the size set in the printer driver is not one the machine can duplex; inkjet models word the same condition as Wrong Paper Size.