What was sold off wasn't the virgin.net platform
Rather it was the old ADSL service (Broadband down your phone line) While the majority of these customers would have had virgin.net email addresses, Virgin Media retained ownership of the virgin.net domain and the email service.
People who were on ADSL who were transferred to TalkTalk were advised that the time that their addresses would close 1 year after they were transferred.
The point is moot anyway, even if the OP was an old Cable or dial up customer, they no longer have an account. The question at this point is how long ago is it since they had one? If it's over 90 days then the account should have been closed.
It might be worth checking to see if the email account is still live, and whether it is possible to give them temporary access in order to recover their emails. So I'm happy to see you are doing this for them.
@jess772 If you click the envelope at the top of the page, you will see any private messages sent to you and can respond to them.
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