Hello yzcsf,
Welcome to the forums:)
I understand you are seeing an error code on your 6500 and before that appeared, you had a paper jam. I would suggest looking at the guide below to troubleshoot.
'Ink System Failure' or a '0x...' or a 'C2...' Error Message Displays on the Front Panel
If the troubleshooting does not help resolve your issue, I would then suggest calling HP's Technical Support to see about further options for you. If you are calling within North America, the number is 1-800-474-6836 and for all other regions: click here.
Regards,