Does anyone know away to find the name of default image viewer etc, in code.
Like if you click on a jpg the default program will open and show image.

Thanks advance.

If you use explorer.exe as the program then it uses the registry to store the file extension mappings. Something like this:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.jpg\OpenWithList



edit: For double click (to run) it goes like this:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\.jpg\(default)=jpegfile

leads to:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\jpegfile\shell\Open\command\(default)=<some program name>

Check also File Types and File Associations for more info.

Thanks, for both your inputs i will look into them.

You can use AssocQueryString to get a plethora of information about what opens what file.