Post Upgrade: When Removing Dated Email Addresses, Tessitura Sometimes Crashes/Shuts Down?

When attempting to delete outdated email, we are experiencing the following:

I clicked on the red X to delete an old email address.  This is the message that appeared:

I clicked on OK.  This is the message that appeared:

I clicked on OK and Tessitura completely closes.

***

The same thing happens if I inactivate the email address & then try to delete it.

The same thing happens if I change the email address to something else and then try to delete it.

***