Cannot Add Internet Accounts I'm running OSX 10.12.6.  For some random reason, my internet accounts pane has cleared &amp; I cannot add any new accounts:



I'm an IT tech &amp; can confirm that I have not manually removed the account. 
 I did have an update the other day, but not sure what it was as I didn't investigate.

iCloud is still registered.

Any thoughts as to what might be causing this?
This answer resolved the issue for me: Can't login with Google using Internet Accounts