I've been working on an HP LaserJet 4100DTN that was giving 51.x errors and print was all mangled. The HP error code indicates that the laser assembly is faulty. So I ordered the assembly and installed it. I printed over 1000 pages since the installation with perfect quality and no error codes. I have banged the printer around and done everything I can think of that a normal user would do and have had no problems.
Why am I complaining, you ask?
My boss just came in and asked about the printer. I told him it was fixed and printing like mint. Does he say, "Good job, Jack! Now I can return it to the customer"? No.
He says, "OK, put the old assembly back in and see if the print error happens again."

Am I missing something here? It's almost a textbook repair but that's not good enough?!? It's not like I have nothing else to work on since he dropped off 6 more machines for me just after telling me this.
Arrrrrgggggghhhhhhhh!
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