Introduction
The PDM 1 and PDM II's PD-Alert feature can send their email notifications to just about every email service. However, some services require specific workarounds due to non-standard security issues.
Gmail
Gmail has a custom security API which is not directly supported by PD-Alerts. However, it does support standard username and password connections if you enable the "Allow less secure apps" option on your account.
The setting is here: https://myaccount.google.com/u/2/lesssecureapps
For more information, see here: https://support.google.com/accounts/answer/6010255?hl=en
Yahoo
Yahoo has a custom security API which is not directly supported by PD-Alerts. However, it support username and password connections if you generate an application-specific password, and use that instead of your usual account password.
For more information, see here: https://help.smallbusiness.yahoo.net/s/article/SLN29264
Hotmail
Our testing shows that Hotmail works as expected with a standard username and password connection.
Other mail servers
Although we have not specifically tested these servers, we believe PD-Alerts will be able to use them as mail servers:
AOL
Facebook
Hushmail
iCloud
inbox.com
mail.com
protonmail
Zoho