@1234Google wrote:
Any help on what to do next would be appreciated
You have given a lot of information there so thanks for that, but just to clarify, this is my interpretation of what you are saying:
"one of my email addresses stopped getting emails I then checked on the server a few days later and there were quite a few stacked up one of my email addresses stopped getting emails I then checked on the server a few days later and there were quite a few stacked up"
1) So the emails are definitely arriving in your Virgin Media account because you can see them when you sign in to the VM Webmail Service https://my.virginmedia.com but Outlook is not picking them up.
"I checked the auto forward settings on the server and that's fine."
2) By that I am assuming you have no auto forward set in your VM Webmail account.
"I then sent email using test email ....... also sent via the other two VM email addresses and all worked and the other two arrived in my Outlook but this one still sits on the server"
3) So, it is only one of your VM addresses where Outlook is not working correctly and that is set up to use IMAP.
However you have confused me when you say "Rechecked settings and these were the same in other VM email accounts and again that is fine too." The reason I am confused is that you go on to say that the problem account and one other use IMAP and the other one uses POP3. However, those 2 protocols (IMAPand POP3) use completely different settings so your addresses that use IMAP cannot have the same settings as the POP3 account. 🤔
The correct settings for both protocols are given here: https://www.virginmedia.com/help/virgin-media-mail-update-settings-in-microsoft-outlook so check that yours match them.
Based on 1), 2) and 3) and that the settings for the problem account match those specified by VM in the link, then the first thing I would ask is whether you are seeing any error messages in Outlook when you use the Start/Receive function to get Outlook to synchronise with your VM addresses?
You should see evidence of that as below where I forced Outlook to generate errors by setting it offline:

Once we know what errors you are seeing that will give a clue to why Outlook is not picking up emails from that account.
Coenoby
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I am just another Virgin Media customer.
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