Ricoh MP C2504 Field Service Manual page 1072

6. Mount the scanning guide plate, taking care not to damage the sheet [A].
7. Peel off the gap sheet [A] from the DF exposure glass with your hands.
8. Clean the DF exposure glass [A] with alcohol.
To avoid paper jams, make sure adhesive is completely removed.
Vertical Streaks on Copies due to Scanning Problems
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