I know of a bunch of symptoms which can cripple your old SLR. From the famous Canon AE1-A1 squeak to mirror frozen in the up position and shutter inoperative. I'll list a few: -No battery (duh!) or old, depleted battery remedy - replace battery -mirror is locked in the 'up' position on cameras with mirror lock-up remedy - unlock mirror -mirror is locked up in any SLR remedies: replace the damper foam, lubricate the mirror assembly (without disassembling the camera, read below on how to do it) -shutter is locked remedies: turn camera on, check batteries, rewind film (if there is film in the camera), check the self timer if it's frozen ========= The damper foam is actually easy to do, you will need some special foam, alcohol (not the drinking type), q-tips, a few fine straight tip mini/micro screwdrivers. PM me if interested and I'll walk you step by step. Lubricating the mirror assembly: Take bottom plate off (set screws in a little jar so you don't lose them). Lubricate every lever and gear you see with one mini drop of Naphta. Try it now (warning: onm some cameras you must have the bottom plate back on before trying this step), if the mirror is still jammed then go to the next step. If the mirror is down and works slow, put the camera on B and lock it there (cable or turn camera off). Now look inside the black chamber where the mirror is. You will see a little arm activating the mirror and coming out through a crescent shaped hole. In that particular hole drop a few drops of Naphta and spray some canned air until dry. Reminder: you must have the bottom plate off so the air can exit without taking the Naphta all over the camera! Now let the mirror come back (tirn on camera, release from B) and that should do it. It works for me, I did two Rollei 35mm SLRs in one hour. Good luck! PM me if you have questions.