Under Setup-> Monitors the "Domain Configuration Status" or "Monitor Configuration Status" can sometimes show an error "Connection Failure" or "Communication Error 403" for one or more TIMs, and using "Synchronize All Monitors" does not help.
The usual root cause for such a problem is a mismatch between the IP Address being used for the MOM or TIM Collector EMs and the corresponding value set on the TIM.
All APM CEM versions
Most 403 problems relate to a mismatch between the IP Address used for MOM or TIM Collector EM's and the corresponding value set on the TIM.
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