I get error code "850 module" when powering on the unit. front panel buttons are unresponsive.
On the 8563E, error codes 800-899 are reserved for errors related to option modules installed in the instrument. If you have the 85620A Mass Memory Module installed, then error 850 means, as it is put in the manual:
There is a note at the top of that section giving a hint for clearing some errors (if the buttons are still unresponsive you could try to do this through SCPI):
If you don't have the 85620A Mass Memory Module, or if the above didn't help, let me know any more information you have and I can try to dig deeper for you.
Also, note that extended service period calibration and repair is available for this instrument. You can send your 8563E to Keysight to have it repaired by our expert technicians while we continue to offer this service.
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