App specific password solves MS Outlook mail authentication problem.

rdfish72 wrote:

App specific password solves MS Outlook mail authentication problem. In setting up MS Outlook could not access iCloud mail - repeated authentication failure with iCloud password. Using app-specific password solved issue. But how was I supposed to know this? If Apple is blocking 3rd party app access to iCloud mail services, is there a place where such policies are published?

Two-factor authentication for Apple ID - Apple Support

Generate app-specific passwords

With two-factor authentication, you need an app-specific password to sign in to your account using third-party apps or services such as email, contacts, or calendar apps not provided by Apple. Follow these steps to generate an app-specific password:

1. Sign in to your Apple ID account page.
2. Click Generate Password below App-Specific Passwords.
3. Follow the steps on your screen.

After you generate your app-specific password, enter or paste it into the password field of the app as you would normally.

LN

Again

With two-factor authentication, you need an app-specific password to sign in to your account using third-party apps or services such as email, contacts, or calendar apps not provided by Apple. Follow these steps to generate an app-specific password:

1. Sign in to your Apple ID account page.
2. Click Generate Password below App-Specific Passwords.
3. Follow the steps on your screen.

After you generate your app-specific password, enter or paste it into the password field of the app as you would normally.

LN