Today I came across an issue where printer auto creation failed for a couple of HP printers on one client computer only. The XenDesktop worker showed an Event ID 1106 stating Printer auto-creation failure. Reason: AddPrinter() failed with status 0x7A.
Searching for this particular error didn't reveal anything helpful. So I had to start digging into it by myself.
Converting hex 7A into decimal 122 and using net helpmsg 122 does provide some additional information:
The data area passed to a system call is too small.
Searching for this error message revelead that there is an issue with the printer or the driver associated with it on the client. It looks like the printer drivers were not installed properly in the users PC. Re-installing the driver on the workstation solved the issue.