[davidmanze]

I can only guess that this is related to IP banning. We are using an external anti-spam service and sometimes it injects IPs. If an IP represents a proxy, it'll ban numerous people behind it.
I've deleted all banned IPs now. Maybe that helps. It helped with JoJu who also had issues with this.

Hi Klaus,

I haven’t been banning ip-addresses for exactly this reason for many years now, just certain email-addresses and email-servers. I you’d like, I could send you my list.

Kind regards, Wim

   I get the same ban situation, sometimes it will block me for half a day......
 
 .....now I have to sign in every time I fire up the computer, in spite of the checked box!