Oki C 9400 - Manual (Page 54)

4. Click File
→ Page Setup and select the size in the Paper drop-down list, then click OK.
5. Click File
→ Print Window.
6. Select Multi-Purpose Tray and Medium Heavy, Heavy or Ultra Heavy in the Paper
Source drop-down list:
7. Select Printer Specific Options 2 from the drop down list and change the Paper Size
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