HP Printer Error - "Unsupported Personality: PCL"
Update from https://www.openprinting.org/printer/HP/HP-LaserJet_1010 (some time in the last several years):
The problem of the "Unsupported Personality: PCL" was finally solved by Carl Michal (michal at physics dot ubc dot ca). By analyzing the output of the Windows driver he found out that after the BeginSession operator in the beginning of a PCL 6 job a special sequence of 8 bytes has to be added. He added it by a filter to the output of Ghostscript's "pxlmono" driver and from then on the printer worked (Implemented as the "pxl1010" driver on this site).
That "pxl1010" driver is https://www.openprinting.org/driver/pxl1010, but it says its deprecated, and hplip (https://www.openprinting.org/driver/hplip/) is the recommended replacement.