I have tried moving senders email address from all emails in the outlook inbox to my outlook contact list three or four times with the same results (see below).
Error message: Outlook experienced a serious problem with Kutools for outlook add in. If you have seen this message multiple times, you should disable this add-in and check to see if an update is available. Do you want to disable this add-in? YES NO
Environment:
Windows 10
Outlook 2010
10,000 plus emails