My canon MX850 indicated a B200 error fault. What is my action to reset the printer? I tried to hold down the on/off switch - switch the power of and keep the on/off switch down and reinstate the power The B 200 error/fault remain We replaced all the ink cartridges and redo the process but without any luck Please help

SOURCE: error code B200 on a

I searched for the error you posted. Cannon wants you to call them. (Weird but true). I'll past the message from Cannon.
Issue: ERROR LCD: Error code B200
Solution: Contact Canon for B200 error (MX850)

Issue: ERROR LCD: Error code B200
Canon has excellent service options and we are eager to provide any assistance you may need. Please contact us through the email link or phone numbers listed below.

• Support by E-mail
• For toll-free technical support, please call 1 (800) 828-4040 during regular business hours (currently Monday-Friday 10:00 a.m. - 12:00 midnight. EST, Saturday 10:00 a.m. - 8:00 p.m., excluding holidays).
  
• Toll-free TDD Support Line for the Hearing Impaired is available Monday - Saturday (excluding holidays) at 1-866-251-3752.
  
• Technical Support is available for Customers in Canada at 1-800-OK-CANON.

SOURCE: Error Code B200

Try keeping the paper only in the bottom tray (there's a tray in the bottom) Try pulling any paper out of the top and just close that top tray. Open up the head so that u can see the ink cartridges and turn the printer on and off and maybe it will center itself again. If it's still not working (even if lights aren't red and print head wont align in the center) try manually moving the head back and forth like 18 times so you can lubricate that rail in the back that's holding it. After that, re-turn it off and on again.

SOURCE: What is error B200 on Canon MX850?

The B200 error is a Voltage High Error. I read that you should try using a different power outlet and see if that works and if that doesn't work try cleaning the print head:

1. Open the printer and wait for the carriage to slide over. If for some reason it does not follow these instructions:
2. • Unplug the printer
   • Manually slide the carriage over until you can get the ink cartridges out.
3. Remove the ink cartridges from the print head.
4. Use cotton swabs dipped in hot water or a mix of hot water and alcohol to thoroughly clean the print head.
5. Repeat this until there is no ink residue coming off on the cotton swab
6. Allow to dry and replace the cartridges
7. Try to print something