Okay, so what I did is I restored the users after creating their domains. Everything works as intendended until I reboot the server, restart Smartermail or upgrade/update it with an update. The moment I do that all those domains and users vanish from SmarterMail. I need to restore / re-attach each user all over again.
Note - that this is only for the case of previously restored / attached users.
If I create a manual new account / domain and user that was never there earlier in SmarterMail (no restorations of any kind), then on restart they exist properly.
Only previously restored domains and users need to be re-attached each and every time after a Smartermail Service restart.
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