Well it takes an experience like this to learn a hard lesson that should never rely on an ISP residential mail service for business critical use. You should always make e-mail arrangements that are resilient and which have an agreed fix time for faults.
Your mailbox has likely been locked for one of two reasons; by VM security because your sign credentials have been compromised and the credentials are being used to send spam. VM need to protect its systems and the internet more widely from this.
Or it is because you are not a VM broadband user and VM are in the process of closing your account as you are not entitled to use their system.
On the assumption that it is the first reason, change you password now in My virginmedia and wait for the VM staff here to pick up this thread in the next day or so and get your mailbox unlocked.
If it is the second, nothing to be done.
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