When trying to save any changes to an escalation in the Set Thresholds configuration screen, an error similar to the following is generated, and the record cannot be saved:
Unhandled System Exception: Action [recid] is not available, please check if it exists and doesn't contain Prompt expressions.
The issue is usually due to escalation notification quick actions being deleted from the system, but still referenced in the escalation schedule. Please try the following;
Click set Thresholds on the escalation schedule
Open the Escalation Level 1, 2, and 3 Tabs
Look to see if the RecID of the deleted quick action is still present in the 'By Running Action' field of one or more of the tabs
Click 'Set as Follows' on the affected tab
Check 'Do not Escalate at this Level'