Hi cathay,

I suggest you to try the following steps:

1) Uninstall the add-on, clean all registry data [start > regedit.exe (run as administrator) > Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\CaptainSim\ x770 and x772], restart PC and install it again, or;

2) If the problem persists, maybe your installer is corrupted.

a) Uninstall the add-on, clean all registry data [start > regedit.exe (run as administrator) > Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\CaptainSim\x770 and x772];

b) Download it again > Check-in to Customer Support > Select product > Extended Download Service > Get New Links;

c) Restart PC and install the add-on from the new installer.

Pinatubo.