Why has my original mailbox login changed after 365?

[UK_Al]

I have had a primary email account for 3 years (myname@btconnect.com) and I am now being told to login to Outlook 365 with a former alias (info@website). I can't set up the original account in Outlook on my PC or tablet unless I use the "info" address, which is confusing my website users and customers as they dont understand why they are receiving emails from the info address rather than my original address. 

Why has my original login address changed, and how can I get it back?

Al 

[anthonyriley99 · Accepted solution]

It's because you have the premium email package with a domain & other features, because of the extras like calendar sharing and push/MAPI server configuration enabled - it's a domain only login at the MS365 end... 

But don't despair!  There is a way round this!  Think of your alias as a login username to your email, when you log in to the 365 webmail you can go to options>account>connected account, enter your btconnect email address details, which you can then set to send and receive using the btconnect email address as default via this login.

[UK_Al]

Thank you for your assistance.

Allan