Yeah, me too! It happens when you actually setup two accounts in Outlook 2010 to connect to Office 365 outlook.com servers. It does NOT happen if you open a second mailbox under the first primary one, but less people do that on Outlook 2010.
Apparently the fix is coming in Office 365 when they upgrade the servers to Exchange 2010 SP2, but I have heard that even then this may not work. The guys on @Office365 twitter account are aware of this, and I have a case open on it they are directly referring to.
The fix I stole from this thread (Brendan Erofeev thanks!), but I wanted to make it a bit clearer.
Essentially, the problem is that the Windows Credential manager is unable to save credentials for two Microsoft Outlook configured proxies. That means that one of your accounts will always prompt you and become disconnected in Outlook. The hack, until Microsoft fix this is as simple as creating a hosts entry to the same IP of your servers proxy and setting that in Outlook. Here is a step by step:
- Open Outlook. Click File, Account Settings, Account Settings….
- Double click on the first account, click on more settings, the Connection Tab, then Exchange Proxy Settings Button. Write down the server name in the “Use this URL to my proxy server for Exchange:“
- Cancel out of the above account. Keep note of the proxy server you just wrote down. Lets pretend yours is msprd001.outlook.com (it will be different than this!).
- Next open up your hosts file on your PC. (If you need to know where this is, click here).
- Open up a Command Prompt on your PC. Type nslookup msprd001.outlook.com and you will be given back an IP address for this server. (Obviously, replace the server name above with the one YOU wrote down earlier). Take note of this IP. Lets pretend its 22.214.171.124 – again, it wont be, this is just pretend 😉
- Now, in your hosts file, add a line that says (remember, use YOUR IP you wrote down):
and another entry
(The 127 address is so that Outlook does not rediscover the corrected settings again from Microsoft).
- Pause for a moment, and take in what we are doing here…. We are creating a false and spoof DNS name “spoofproxy.outlook.com” for the same IP address of your actual servers proxy. This will mean we can use this proxy in the second account in outlook and Windows will save your password and all will work properly.
- So, again, follow the pretty path in the image I spent hours creating on step 2 above…. but this time do it on the second office365 account in outlook. When you get to the last step of the arrows, you change the name there, and only there, to spoofproxy.outlook.com
- Lastly, and importantly, you need to add a loopback IP for autodiscover to the hosts file.
- If you followed this correctly, you should now restart outlook and have two working accounts.
If your computer self combusts, explodes or in some other way disintegrates, you cannot hold me or anyone at NTES responsible!