HT1277 BT have confirmed all settings are correct. Contact Apple, see if they can sort it......

Question

I cannot receive webmail from BT office 365.  iMail is unable to receive emails.  All my settings/preferences are correct.  They were confirmed by BT!  Bt operative told me to seek help from Apple!  What do I do?  BT set up iMail using screenshare, before you ask.

Answer 1

This is a user forum, and not a formal channel into Apple support.  If you're looking to discuss this with Apple Support (which I'd infer was what BT had intended), then you'll want to contact Apple support directly, either by phone, email, or the Genius Bar at an Apple store.
You have written that you cannot receive "webmail from BT office 365", but there are few details on how that mail is being routed and received.  I'm going to make some guesses here.
In general, you cannot receive web mail directly - assuming that this BT office 365 is a typical web mail system - as there needs to be a mail server involved somewhere.  I can't determine from what you've posted and what I see on the network if the mail server you're referencing might be the same server as is used by "BT office 365", or if it could be a different server.  If it's a different server, then there are other places that mail can be dropped.
Based on what I see on the net, this BT office 365 web mail package appears to be the Microosoft Office 365 package.  If that's the case, then Microsoft has troubleshooting information available, and also has information on determining the proper mail server settings for Apple Mail.
If the server behind the Microsoft Office 365 mail system at BT is the same mail server that you're using here (amd as I might guess), then the issues are within BT's network, or with the network connectivity from your network into the BT servers.  Its also quite possible that there are firewall or other blocks operating within your local network, or in the path to the BT servers.
Connectivity can be verified -- that's something that a typical front-line support call would try and resolve - but I don't know if that testing has happened here.  Basically, there would be an attempt to connect into the ports made directly, typically using either telnet to the target port, or openssl s_client connect to the target port for SSL-based connections.  This to determine if the port is blocked or not.
Given that using telnet or openssl s_client are tools that you probably don't want to start out with, start with the above Microsoft documentation for the proper settings, and try the Apple Mail Connection Doctor tool (Mail.app > Window > Connection Doctor), and see what that reports.
If the error(s) or problem(s) you're encountering here are not a baseline mail configuration error (and if there's more than one mail server involved), then it's quite possible for mail from one mail server to be rejected by another.
And if you continue to have issues, contacting Apple Support directly might be helpful; you can share credentials and server-related information with them, and that can greatly speed up the troubleshooting process involved here.