Session timeout- cannot access web site

"Session Timeout
Your session has expired. To protect your personal data, the system
automatically expires your log in session after a short period of
inactivity.

To continue using the system, you will need to log in again."

I joined the MBNA Bank and successfully accessed their web site. Suddenly I
get the above message and cannot access their site.

I have phoned MBNA and also written but so far only a promise to look into
it wife an ominous silence. Strangely they do not have an email service for
such a major Bank.

Is there a setting in Internet Explorer which might be doing this or is this
an MBNA problem?