I have exactly the same problem and need help.
Error message: "an error has occurred while trying to add the selected printer. Error:- 50."
I am unable to add my printer (HP Laserjet 1320) to my computer (Mac 10.4.10) even with the latest driver for this printer (5522.dmg).
Here is the pathway that causes the error message:
printer browser - protocol - line printer daemon (LPT) - print using HP (HP Laserjet 1320 series) = error 50 message.
I've tried the following things to fix the problem without success:
- resetting the printer system (applications - utilities - printer setup utility - reset printing system)
- uninstalling the printer software by deleting it from the applications folder, then putting it back in applications by downloading the latest copy from the hp driver page
- unplugging then plugging the printer back in
The main question is: what is error 50 in relation to printer installations?
Has anyone ever experienced error 50 before with printer installs with the Mac ?
Thanks for any tips on solving the error 50 error message when installing a printer on the Mac operating system. Note that I am not on a network. I'm just connecting one printer to one computer.

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