I have an HP C5550 all-in-one. When I try to print, it gives me a paper mismatch error. I am using plain old 8.5 x 11 paper, I checked the properties box, it is set correctly. I followed the HP guided solutions, none worked. I tried disconnecting and reconnecting printer, everything. It will let me copy a page, however it will not let me run a self-test (same error, even with the printer disconnected from the computer). Any ideas?

SOURCE: Printer not working...

Press Enter and Menu simultaneously when align message is prompted on the All-in-One.

SOURCE: Paper mismatch

I just went thru this same problem and I spent 1 hour with HP customer service and we came to the conclusion there is a malfunction with the printer's main sensor. They are sending me a new printer. I also had a problem with making copies and it would only print out 1/4 of the page. I think the sensor is TOO sensitive and if you get a paper jam and you try to pull it out, it creates a problem with the sensor. I suggest two things #1. call HP and go thru the 1 hour and they will determine the same and they will send you a new printer. #2.You can wait, if you have a spare printer, until I receive mine to see if the same thing happens. It could be a defective sensor with this model. I have an older HP PSC 750 and it still works great!

SOURCE: Print Envelopes with hp c309a "Paper Mismatch" error

Even though the icon on the printer shows the envelopes entering the printer narrow side first, you have to set the printer up for, and feed the envelopes through, wide side first.

SOURCE: Try to print but: get General Printer error 0x61000f6 beware spam number 1*800*532*4187

Hi

This error comes due to carriage jam. Turn off the printer and unplug it from wall socket. Now, remove the cartridges and check for any dried up ink residue on cartridges on inside the carriage. Clean the cartridges contacts and carriage using a Q-tip dipped i alcohol. Let the carriage and cartridges dry before you plug in the printer.
Install the cartridges and check. If it still shows error then unplug the power cord coming to the printer without switching it off. Now, remove the rear door of the printer and check for any paper jams over there, remove if any. Wit for at least 15 seconds and plug in the power cord. Now check whether it is working.

Daniel Scott

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