Mail.app on iOS: Cannot move mail from IMAP to greyed out Office 365 mail account

Hi There, I signed up just to reply to this thread as I just spent quite a bit of time being completely infuriated as to why this simple operation would not work.

I also found the only reply on this to be completely unhelpful, to say the least.

I had the exact same issue as yourself when trying to compile all of an employee's POP3 emails into their new Office 365 service. I added the office 365 account as exchange on the iPad as it should be and then attempted to move all of the sent emails from the iPad onto the exchange mailbox.

I had the same greyed out issue and spent quite a while pulling my hair out trying to find out why this would not be allowed.

I eventually decided to try and remove the mailbox as exchange on the iPad and then add it back in as an IMAP account. Bingo, the account was no longer greyed out and I was able to transfer all of the emails across to the new account. Once the emails have been transferred you can simply remove the IMAP mailbox and re-add it as exchange.

For anyone who needs to do this I will save you some time and place the imap settings for office 365 below.

Hopefully this saves someone a lot of unnecessary stress.

Server name: outlook.office365.com

Port: 993

Encryption method: SSL

Cheers.