Problems with .acsm file

Hello,

I've purchased the book "The Shepherd" with my LG 500 Android device.

The downloaded format is .acsm which I can't open in Aldiko.

I've tried to use Astro, reinstall Aldiko - but both of them didn't help.

I was registered with my Adobe ID all the time in Aldiko.

Please help me open "the Shepherd" book in my mobile device.

Thanks

Shlomo
cshlomo2@gmail.com