The user is trying to download AOL messages but having no luck (Authentication Failed).
The user definitely used the correct user name and password.
An error has occurred. Authentication failed. Check username and password. The server returned: [SYS/TEMP] Server error Please try again later.
According to AOL documentation:
It should be possible to access your mailbox with the correct credentials,
which is full email address and password.
In future, Verizon - which scooped up Yahoo and AOL, may require 2FA verification -
2FA = 2 Factor Authentication
Here is the relevant extract:
...Which apps require application-specific passwords? Apps that require an app password include: * mobile Mail apps: iPhone / Android / Windows and others * desktop Mail apps: Outlook / Thunderbird / Mac and others. * Calendar and Contacts apps The AOL app for iPhone and Android does not require an app password.
MailStore Home classifies under “others” in the second bullet above.
This is a good practise to use 2FA. Many email providers adopt or offer this authentication mode - some make it even mandatory. Some provide the 2FA directly under the security settings of your account.
Provide the name of the app (like “MailStore Home”) and then “generate” the application based password. This application connected password (in short “App Password”) is then used as the in MailStore Home password.
Please note, that login to your account for webmail and to work on 2FA settings still requires your regular username and password.
Special thanks to @DiggerP for research and collaboration in the discussions that lead to this article.