Hi DH,
I'm glad to hear that you have fixed the issue.
We can use the Remote Connectivity Analyzer (RCA) tool to get the server settings. I will give you the detailed steps about how to manually configure Office 365 account in Outlook client:
1. Use the remote connectivity analyzer via www.testexchangeconnectivity.com to test the Outlook autodiscover. Please choose the Outlook Autodiscover option under Office 365 and click Next. Please refer to the picture below. Type email address, Microsoft account, password and verification code into the bar and click Perform Test.
2. After the test finish, please click Expand All option on the right side of the page. Please look for <Server> and <PublicFolderServer> under Additional Details, and keep notes of these two server address. For example, <Server> is 1b5aee53-8734-4b91-92da-d6ea827b3880@xxxxxxxx.com and <PublicFolderServer> is xxxxxx.outlook.com.
3. Click on Start, go to Control Panel. Click Mail> Show Profiles> Add.
4. Type a name for the profile you are going to add, and then click OK.
5. Select the option of Manually configure server settings or additional server types and click Next. Click Microsoft Exchange Server or compatible service> Next.
6. In the Server box, type the host address that you took note of the <Server>. Make sure that the Use Cached Exchange Mode is checked. Type your Office 365 user name into the User Name box and click on More settings.
7. Click the Connection tab, make sure that the Connect to Microsoft Exchange using HTTP check box is selected, and then click Exchange Proxy Settings.
8. In the Use this URL to connect to my proxy server for Exchange box, type the host address you took note of <PublicFolderServer>. Check the box of Only connect to proxy servers that have this principal name in their certificate and file the bar with msstd:outlook.com.
9. Check the two boxes of On fast networks, connect using HTTP first, then connect using TCP/IP and On slow networks, connect using HTTP first, then connect using TCP/IP.
10. Choose Basic Authentication under Proxy authentication settings and click OK.
11. Go to the security tab and make sure all of the settings are as same as the picture below.
12. Click Check Names. When the server name and user name are displayed with an underline, click Next> Finish.
Regards,
Jerry Cen