Printing & copying blank pages

Change Toner.

You have to disassembly and clean scanner as well as document glass from other side

its probably set to a low DPI.......change your dpi to like 600 when scanning

toner or drum?? if toner the chip may be defective or wasnt changed at refill. if its the drum, print the help page to guide you to that section. and reset.

I would first of all Go to the Xerox.com site and go to Drivers and downloads for the M20i and install the newest firmware. I believe the current version is 3.4.
I believe your problem would be resolved in loading the newest machine firmware.

Since you cleand the scanner and scans are fine, the other item I seen cause that problem is the power supply.

yes directly

If the issue is only when you are copying, the scanner needs to be cleaned.
If the defect is on both copies and prints, and fax if you use it for that, then your problem is either the drum or toner cartridge or the laser is dirty.
I am not sure when you say you changed the print cartridge if you mean you just changed the toner cartridge or the drum cartridge.

someone has gone into diagnostics and enabled Status Print Engine
Fix
1. press menu/exit key
2. enter # 1931 in that order
3. engine test(diagnostic) should be displayed
4. use arrow keys to scroll to, then select engine test(status print)
5. press enter
6. press the "2" key on numeric keypad to disable (status print)
7. machine will revert to Ready to Copy
8. power off and then back on the M20
9. Your done.