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Questions & Answers
Q: Don't know what I did to my dell 3100cn laser printer. I'm now getting a "004-321 restart printer". Can't get past it. Also, is the same printer compatible with my MacBook Pro? How to fix 004-321 error on my Dell 3100cn Laser Printer?
A: It seems like the problem in your printer's drum. We suggest you to please detach the drum from the printer and then re-place it again properly. Do same with the toner cartridge as well. Here's Dell's official guideline on how to fix 004-321 Error on Dell 3100cn laser printer. You may apply the power drain to your printer.