Good morning.
I moved my email domain from 1and1 hosting over to Office365 about a month ago. Overall I am pleased with the reliability, but I have had an issue.
I am using Outlook 2007 (12.0.6668.5000) SP3 MSO. When I open Outlook, it asks me for my Office365 username and password, but it also asks me for my old 1and1 email login credentials. I can tell because it mentions server 'exchange.1and1.com'.
When I setup Outlook for Office365 email, I completely deleted my old Mail profile in Windows Control Panel that had the 1and1 server information, and created a new profile from scratch, where I setup my Office365 server information. It connects to my Office365 exchange server just fine, but something is still configured that asks for the old login credentials.
I have my old 1and1 emails loaded in Outlook as archived .PST data files, and the only other data file loaded is my offline sync .OST file. I have done searches in the registry for the string '1and1' and found nothing at all. Some of the research I did on this issue mentioned possible changes in server settings on the old server, but since my previous server was hosted through 1and1, I don't have the ability to manually change any Exchange Server settings.
I am looking for some assistance on how to either prevent Outlook from requesting the old server login credentials, or even something as simple as permanently disabling the popup window. It seems to come up every 10 minutes or so.
I will be glad to provide any further information, and any help would be most appreciated. Thanks.