SquirrelMail: Mail directory exists but shows up empty when logging in

[ATC]

When logging into squirrelmail on a server using virtual accounts (from AD, LDAP or any other external source) all the user's email appears to have disappeared. All custom folders are gone, and the standard folders are empty.

When manually checking the server, the user's home directory, custom folders and messages are all there.

[ATC]

The user may have logged in using uppercase letters in the user name. By default, squirrelmail preserves case and some password backends (such as AD and LDAP) are case insensitive.

This means the login is authenticated but since the web server is case sensitive the login name does not match the existing home directory.

Edit "/etc/squirrelmail/config.php" and set "$force_username_lowercase ) true;" and log in again.