@TJH-L
The problem is that it's a workaround you are using rather than a proper fix.
This isn't as simple as a dodgy certificate though. We'd have considerably more threads on the subject in a very short space of time if this was the case.
Add to that - I sill have a Blueyonder email account (not for much longer though as I'm no longer a VM customer :() And I'm currently able to access it with no issues using imap.virginmedia.com on port 993. I've also pulled the certificate chain from the server.
The only possibility I can think of is that somehow the root certificate no longer exists in the Windows trusted root store HOWEVER the error message doesn't seem to match this.
Tim
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