Taken from: http://paperworlds.papermakeit.com/

Gimp uses Ghostscript to import pdf files and transform them into images. Im most linux distributions ghostscript is installed by default or pulled into the system as a gimp dependency. Unfortunately it’s not the case in windows enviroment. In order to get pfd importing in gimp you need to install ghostscript manually and tell gimp where it can be found.

I presume You have gimp already installed

  1. Download and install Ghosttscript
    • Go to http://sourceforge.net/projects/ghostscript
      • Look for package Ghostscript x.y
    • Download a prepared Windows distribution (e.g. gs861w32.exe)
    • Start the executable and follow the instructions of the installation procedure
  2. Copy the executable `gswin32c.exe` (not the `gswin32.exe`) from the directory `c:/program files/gs/gs8.60/bin` of the ghostscript installation to the Windows directory (e.g. `c:\windows` or `c:\winnt`). (Creating a shortcut would work probably too)

    You don’t need to do this, since we are going to add location of gswin32c.exe into PATH variable in windows.

  3. Tell windows where Ghostscript executable is installed
    1. Open the Control Panel
    2. Double click on System icon
    3. Go to Advanced System Properties
    4. Click on Environment Variables
    5. Click on New button of System Variables
    6. Set Variable name: GS_PROG
    7. Set Variable value: C:\Program Files\gs\gs8.61\bin\gswin32.exe (check the version: 8.61, 8.62, etc.)
    8. Click on OK three times

Now it should work.

Update: 02-01-2012

Last step is probably not needed on Win7, since I got Gimp to import pdf files, without setting the variable. I don’t know if it is related to gimp, ghostscript or windows itself though.