List current filetype associations with these two different commands:

ftype
or
assoc

Change or create new ones:

Open an elevated command prompt.

• Use FTYPE {fileType}={commandString} to create a file type and associated command to open the file.
• Use ASSOC {.fileExtension}={fileType} to associate a file extension with the file type you created.

Example:

FTYPE MyCustomType=C:\Program Files\MyCustomProgram\MyProg.exe “%1”
ASSOC .custom=MyCustomType

These commands can be issued from the KACE server. See the SPSS example there.