Do you have installed Blender, or any other product that requires Python 2.6 ? Or you might have installed Python yourself ? it seems your other Python install is clashing with Couatl, because it's looking into your actual Python installed folder, when it shouldn't...
Check if you have some environment variables set to point to that folder:
- Open a Command Prompt
- Type SET and press Enter
- Look if you see any variable that sets a path to the C:\Python26 folder
this is the python entry I get:
Let me know if you need more info.