In my home office I use a laptop, my wife a desktop. We both were using Outlook 2010 as our email program, we both had 2 business accounts and 1 personal. Her computer crashed. She installed Office 2007 in the new machine, as 2010 had been supplied by Comcast. Both machines received the same emails and we each dealt with them as necessary, she would file some, delete some and me the same without it affecting the other. I was still on POP3 and she IMAP. We thought it was a 2007 problem, so downloaded 2010 again and the problem still persists.
We spoke at length with Microsoft yesterday and they consider it a problem of IMAP. I haven't spoken again to a Comcast tech but wanted to ask if anyone else has a similar happening. If there was a sole user for both of these machines it would be fine, but there is not. It didn't do this before when we used POP3 setting.
Any suggestions? Thank you.
Anytime a particular email account is accessed from more than one device - phone, pad, or computer - the most trouble-free setup is configuration of every device to use IMAP. The interchange between the email client and the server is very different between POP and IMAP. Only IMAP will present the same set of messages to all clients, including changes from any client. Connections to Exchange servers using non-POP Microsoft protocols behave like IMAP connections. As with IMAP connections, all clients see the same view from the server.
If an email account is accessed from only one device, than all this makes no difference, except that recovery from local mailbox corruption is possible from IMAP servers since messages are normally only deleted from the server when deleted from a client. With POP access, messages may be deleted from the client or server independently. In this case, confusion often abounds.
It should be noted that this a mail client to mail server protocol issue. The above comments apply equally to any working Outlook vintage and other clients like Thunderbird and macOS Mail.
Bottom Line - Use IMAP, not POP if you have a choice. And of course, Exchange with Comcast Business email.