"Disk images failed to mount" "Not recognized"

Hi,
I am using MAC OS X 10.5.8 and installed the trial version of Espionage a few weeks back. It expired and I attempted to restore the ".dmg" since it was not accessible. I uninstalled Espionage hoping that the file would automatically restore. Then I reinstalled and tried reopening once again and got the following error box "The following disk image failed to mount" and the reason stated is "not recognized." I have also tried re-encrypting the file and no luck.
This is the only copy I have of the contents, so I will be thankful for your help with this.
Thanks
I am using MAC OS X 10.5.8 and installed the trial version of Espionage a few weeks back. It expired and I attempted to restore the ".dmg" since it was not accessible. I uninstalled Espionage hoping that the file would automatically restore. Then I reinstalled and tried reopening once again and got the following error box "The following disk image failed to mount" and the reason stated is "not recognized." I have also tried re-encrypting the file and no luck.
This is the only copy I have of the contents, so I will be thankful for your help with this.
Thanks