From the help docs:

Click Banking, and then click Account List.
Click the name of an account that's set up to receive online account updates.
In the left pane under Other tasks, click Change account settings.
Under Online Services, click Change bank or brokerage passwords.
Type your updated password or sign-in ID exactly as you did when you changed
the password on your bank or brokerage website. Or, if you are prompted,
click Edit password, and then follow the instructions on the screen.
When you're finished updating your information, click Save Changes.
Notes

When you delete a password, the password may still appear until you restart
Money.
If you add a password and choose not to have Money remember the password,
the password will still appear until you close Money.

"BankZ" wrote:

- quote -

I have to change my user id for my bank login. However, the only option I
see in MS Money is to change my password. I don't see a way to change my
banking login. Whats the best way of doing this w/o losing all my data?