Canon 7 How To Use Manual page 25

When you have finished a roll of film and you try to advance the film. You will feel tension on your
finger. You should then stop winding and remove the film from the camera in this manner:
Pull out the rewind crank as far as it will go and take out the film cassette or magazine.
Be sure to put the lens cap on before rewinding the film.
If the film is forcibly wound after all exposures have been completed, it will be impossible to rewind the film.
It will have to be taken out in a darkroom.
'
24