This message is displayed if your anti-virus or anti spyware application is conflicting with our Viewer application.
Disable your anti-virus anti spyware application when installing / registering the Viewer software and then enable it again once installation is complete.
There is a known issue with an antivirus program called “PC Tools Internet Security” which conflicts with our Viewer application and needs to be disabled when installing and registering the Viewer and when opening protected documents.
Windows Server 2008
If you get this error message when trying to open the Safeguard Viewer on a Windows Server 2008 R2 Standard / 64 bit OS then use the compatibility troubleshooter and run the installer in a compatibility mode. Configure pdcviewer.exe to run in compatibility mode for Windows XP SP2.