All folks here know how stupid is to fool yourself.
Nonetheless it happened to me 2 times in last months to try to enter CE mode on bizhub C250i and cannot.
The reason was that in all my stupidity I was left PSWC logged in Administrator mode.
Draw a lesson and save some minutes next time you cannot enter in CE password screen, check for PSWC session logged in Admin mode. If so logout and try again.
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