HP Compaq dc7900 USDT Technical Reference Manual page 102

Error Messages and Codes
Error Message
1801-Microcode Patch Error
Invalid Electronic Serial
Number
Network Server Mode Active
and No Keyboard Attached
Parity Check 2
A-4
Table A-2. (Continued)
Power-On Self Test (POST) Messages
Probable Cause
A processor is installed for which the BIOS ROM has no patch.
Check for ROM update.
Electronic serial number has become corrupted.
Keyboard failure while Network Server Mode enabled.
Keyboard failure while Network Server Mode enabled.
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