Can't advance film, press shutter, no result
Do you have film in the camera? If so, is it an old film or you have just loaded it?
If it's an old film, could it be at the end of the roll - to check this, 'lightly' turn the rewind lever backwards and forwards. As the camera is pointing away from you, turning the rewind knob clockwise will normally rewind the film (don't press the rewind button in, we don't actually want to rewind the film yet), turning the knob clockwise should be tight and a firm stop, if the film is at the end, you will feel the same tight firm stop if you turn it counter-clockwise. Don't turn the rewind knob backwards (counter-clockwise) too hard, you'll unscrew it and it may fall apart. If turning it backwards rolls freely in a full circle, then you have film left.
Another option is that, since it's been so long since you used it, the loading of the film may have gone amis and sometimes the cassette will flip backwards, jamming the film in place so it wont advance - if you have loaded the film and not taken any pics or have not been able to advance it at all, it should be safe to open the back as the film will be in it's original loading position, if you have left the film in it from some time and don't know what stage it's up to it may be best to take it to a camera store where they will have a "Black Bag" to put the camera in and manually open and unload the film. Make sure you get an experienced person - some pimply-face teen that's never used a film camera can easily put their fingers through the shutter while it's in the black bag - I've seen it plenty of times.
OK, that's enough to get started, did this work or do we need to try more options?
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