Windows Live custom domains: Invalid Credentials

I’m getting “Invalid Credentials” when connecting a Windows Live Domains account. How can I fix this?

Unfortunately Mailspring doesn’t support connecting Windows Live custom domains accounts, since they’ve been deprecated by Microsoft.

However, since those accounts aren’t much more than aliases to a regular Outlook.com account, you should be able to connect your original @outlook.com account and to set up aliases within Mailspring.