Canon PIXMA MG2525 All-in-One Inkjet Printer (Black) - Manual (Page 160)

Cannot Scan Multiple Items at One Time
Check 1: Make sure that the items are placed correctly.
Placing Items (When Scanning from a Computer)
Check 2: Check if you can properly scan one item.
Some applications do not support multiple image scanning. In that case, scan each item
individually.
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