source: https://www.securityfocus.com/bid/8449/info
It has been reported that a password disclosure issue exists in CheckMail allowing a local user to access sensitive authentication information through the Windows Registry. The software stores user authentication credentials in a Windows Registry that can be viewed by a local user in order to steal e-mail passwords.
This issue could lead to further attacks as a malicious user may gather sensitive data through user e-mails.
It should be noted that the issue has been reported in CheckMail v1.2, however older versions may be vulnerable as well.
Windows Registry key used to store passwords:
HKEY_USERS\S-1-5-21-823518204-436374069-1708537768-1004\Software\DeskSoft\CheckMail