1. Password not accepted but later found ok and accepted
It would be helpful to see what, if any, error code is returned by the SMTP server in this situation. From a desktop or laptop device open a Command Shell in Window or otherwise a Terminal. and enter the following where username:password is replaced with your email address and password, i.e. firstname.lastname@example.org:Y54kpX5g:
curl -v smtps://smtp.virginmedia.com -u username:password
Do not post the resulting output here but instead review it for possible reported causes and then post just that here or the VM error code; ignoring this advice and posting the output here unredacted or incorrectly redacted may reveal your email address, password and / or public IP Address.
2. Incoming mail sometimes delivered to archive, sometimes to draft, sometimes to spam.
With no filter rules being defined in webmail look at other email clients used with the account for possible explanations.
3. Outgoing/sent mail sometimes appearing in deleted items folder or disappearing altogether.
Again, look at other email clients used with the account for possible explanations.
If the issue still remains unexplained then consider following the advice here, My Virgin media email has been hacked | Virgin Media Help
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