This was driving me crazy I tried repairing, uninstalling, other things, but nothing worked permanently. Finally I found a solution that just works:
Just delete this folder and the problem will magically go away:
C:\Users[[[Your Account]]]\AppData\Local\Temp\wlmailxxxxxxxxx
Note:
[[[Your Account]]] = Your Windows account
wlmailxxxxxxx = wlmail<number here>
Andrew