Your PATGuard database will be stored in the install directory unless this is changed by a user. Please note the install directory could also have been changed during the installation process.
By default the install directory where your database(s) are stored is as follows:
C:Program FilesSeawardPATGuard 2
If you have an older program then your program name will be in place of PATGuard 2 - such as "PATGuard Elite" or "PATGuard Plus"