Is this a gmail or outlook.com/Hotmail account?

This is a virginmedia.com account.

On the Virgin Media Community Forum, there is a topic where it is stated that - "To ensure the Virgin Media Mail migration from Google was completed successfully, we had to make some customisations to the way email clients use the POP3 protocol with our servers. This has meant that deleting emails in an email client using POP3 doesn’t delete the emails from the server, but hides them from the client and so may be viewed when accessing the mailbox using webmail. This is similar to the way the previous Google platform worked, but differs from the standard POP3 behaviour. Virgin Media are focused on providing the best possible experience and functionality for customers using our products and services and we will continue to review the Virgin Media Mail service, including how we use the POP3 protocol, but are unable to align fully with the standard POP3 behaviour at this time. We strongly recommend Virgin Media Mail email client users access via the IMAP protocol, or alternatively use webmail. Both of these access methods will fully delete the mails from the server."