HP dx7300 Technical Reference Manual page 156

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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