Emails not being received by newly created alias account - Microsoft Community

i tried sending email 1 of newly created account aliases (these accounts visible here https://account.live.com/names/manage , there no copy paste error, account exist sure), have got following error:

col004-mc2f48.hotmail.com rejected message following email addresses:

*** email address removed privacy *** (*** email address removed privacy ***)
your message couldn't delivered. appears email address sent message wasn't found @ destination domain, or recipient's mailbox unavailable. email address might misspelled or might not exist. try fix problem doing 1 or more of following:

• send message again. before do, delete , retype complete address. if email program automatically suggests address use don't select it.
• clear recipient auto-complete list entry in email program following steps in this article. resend message, before do, delete , retype complete address. if email program suggests address use don't select it.
• contact recipient other means (by phone, example) confirm you're using right address. ask them if they've set email forwarding rule forwarding message incorrect address.

if you're still unable fix problem, ask recipient tell email admin problem, , give them server reported error below.

for email admins
when office 365 tried send message, external email server returned error below. error reported email server outside office 365, , if sender unable fix problem correcting recipient's email address or clearing auto-complete list entry, it's problem recipient's email admin can fix.

• check error information problem happening. for example, domain name. domain name tell organization responsible error. recipient's email server causing problem, or due third-party service organization or recipient's organization using process or filter email messages.
• if can't fix problem, contact responsible party's email admin. this recipient's email admin, smart host service admin, or similar. give them error , name of server reported error them troubleshoot issue.

unfortunately, office 365 support unlikely able these kinds of externally reported errors.

col004-mc2f48.hotmail.com gave error:
remote server returned unknown recipient or mailbox unavailable -> 550 requested action not taken: mailbox unavailable 

hello mmprops,

based on error message, seems outside hotmail server cannot find correct email address, genereate error message.

so, in order make sure email address valid , contactable, let new created mailbox send email office 365 account, reply email. succeed time? 

could please share entire ndr original message header in it? send private message collect it. can try using other mailboxes let me know if email can delivered target address.

best regards,

alison

Office / Office 365 for business