OE6 cannot connect to mail server after login change

I am getting 'failure to connect to [mail server]'
on pressing the Send and Receive All button.

It doesn't make sense.
It happens after I log off and then log on.
I am the only user, and I have administrator rights.
Otherwise mail still works, I just cannot log off then log on.
It has only been happening for the past two days.

The last thing I did with Windows XP was install 4 security updates
that came together.
I have tried uninstalling and reinstalling all related software, OE6,
software modem, updates.

What actually changes on relogging in? It is the same user before and
after, me.

Thanks.


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