How to save your password for outlook when using RPC over HTTP

When using RPC/HTTPS connection in Outlook, you will need to follow the instructions below to store your password so Outlook will not prompt you for credentials. You must be running on Windows XP or Vista (any edition except Windows Home).

1. In Outlook,  Go to: Tools > Email Accounts > Click Next to View or change existing email accounts > Highlight Microsoft Exchange Server and click Change > Click More Settings > Connections tab > Exchange Proxy Settings.
2. Select NLTM Authentication as the Proxy Authentication Setting
3. Check Connect using SSL only and Mutually authenticate the session when connecting with SSL
4. The Principle name for the proxy server is in the following format:
   • msstd:proxy.server.com (proxy.server.com is the same as the Proxy Server URL)
5. Click OK and close all the Outlook Settings Windows
6. Launch Outlook, and when prompted for your username and password, make sure to check the box ‘Save Password’ and login.
7. In Windows, click the Start Menu > Run > Type in “control keymgr.dll’”
8. You’ll see an entry now with the Exchange Server name. Select it can click Properties
9. Change the first portion up to the first period ‘.’ with an asterisk ‘*’. Below is an example:
   • “Exvmbx017-10.exch017.msoutlookonline.net”  should be changed to “*.exch017.msoutlookonline.net” (without quotes)
   • For Windows Vista you will need to Add a new entry. For the Log on to field, you will need to replace everything up to the last period with an asterisk “*”. Example: ”*.msoutlookonline.net”. Credential type should be set to “Windows Logon Credential”.
10. Enter in your password and click OK
11. Reboot the computer.

**Note: Only one account/password can be saved per Windows Profile**

If you are missing the Add button you may want to modify Windows Registry to save the password. Note, that for editing Windows Registry administrator rights are required, because it is not safe and you will perform it on your own risk.

1. In Windows, click the Start Menu > Run > Type in “regedit”
2. Navigate to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Lsa\
3. Find DisableDomainCreds entry. Value of 1 (enabled) will prevent you from saving new credentials.
   Cange the value to 0 and reboot. You should have the Add button. Note, that the value of 0 is the default value.
4. Also check LmCompatibilityLevel entry. It should be set to 3, which is a default value. If you have another value, change it to 3. If it does not work with 3 then also try it with 2.
5. Reboot the computer to apply changes.

See http://www.intermedia.net/support/kb/default.asp?id=1399 for more information.