Saying "the results were bad" is of absolutely no help. Exactly
what was wrong with the prints?
There is nothing in a Polaroid 100 that senses the presence of film so there is no way that loading film changed the way the shutter functioned.
The best quick check of the shutter's function is to cover the meter cell with your finder and seeing if the camera makes a rather long exposure when fired. You hear two clicks (one for opening and one for closing) and be able to see light through the lens during the "exposure".
Common failure points on most of the 100, 200, 300, & 400 series:
- weak or dead battery
- corroded battery terminals
- corroded wiring leading from the battery terminals
- dirty switch contacts in the shutter
This last one can be addressed fairly easily. You can open the shutter housing by removing the screws on the back of the housing. You should be able to easily see the open switch contacts that are operated by the cable release coming from the shutter button. Gently cleaning these with denatured alcohol on a piece of cotton cloth should work. Don't use anything more abrasive than a paper towel.
If there has been a history of batteries leaking, simply cleaning the battery contacts is very often not enough. The corrosive material leaking from the battery will very often wick up into the wire causing it to fail inside of its insulation. The only solution is to replace the wire, either all of it or at least a long enough length to get past the corrosion.