Our university president is having issues adding actions. As system admin I have made no changes to his user rights.
He reports that the “Add Action” button is gone from the constituent record page. He needed to click the link to the existing actions to get an “Add Action” option. When he entered the action (Category - Mail) including all the required fields and goes to save he is getting this error message.

I looked in KB but this specific error is not listed. He has added actions before. I do not know what is different this time. Can a user be restricted from choosing a certain type of action from the dropdown list?
I've asked him to try adding actions on other records with different types but do not have a response yet. Told him to restart computer
Seems odd that the option to ‘add action’ is no longer on the main record page.
Any ideas? Not looking forward to lengthy session with support as president is in another building and I don't want to tie him up for a long time if I can avoid it.