How to recreate the BPOS Outlook profile

The Microsoft Online Services Sign In client does a once-only configuration of Outlook when you first sign in to create a BPOS profile. If that profile is subsequently deleted, Outlook will refuse to start with "The profile name is not valid", but the Sign In client gives you no option to recreate the profile.

You can quickly recreate a deleted profile using the following command:

outlook.exe /importprf "\Users\<username>\AppData\Local\Microsoft\Sign In\Config\<email address>\outlook-configuration.prf"