CallPath response message: cannot set MWI
A negative CallPath response corresponding to an earlier SLTPIND (MWI) call, indicating that CallPath could not set the MWI to the requested state. The MWI number and other details relating to the earlier STLPIND call are printed in the error.
STLPIND sets or resets an MWI indicator on a phone.
Check that the phone number for the STLPIND request is valid.
Yellow (error_id = 20503)
Log, System Monitor