A garage door that refuses to open is frustrating, but it is not always a major fault. Before you call for help, a few safe checks can reveal whether it is a simple fix or something that needs a professional. Work through these in order.
Start with the obvious - Is the remote dead? Try the wall button. If the wall button works but the remote does not, replace the remote battery. - Is the door locked? Some doors have a manual lock or a vacation lock mode on the opener. Check it is disengaged. - Is there power? Confirm the opener is plugged in and the outlet has power; a tripped breaker is a common culprit.
Check the safety sensors Modern openers have two small photo-eye sensors near the floor on each side. If they are misaligned, dirty, or blocked, the door will refuse to close (and sometimes behave oddly). Wipe the lenses and make sure they point straight at each other; a steady light usually means they are aligned.
Look and listen - If the motor runs but the door does not move, the trolley may be in manual-release mode. Re-engage it per your opener's instructions. - If you hear a loud bang followed by a door that will not lift, you may have a broken spring. Do not force it. - If the door is crooked or off its track, stop using it.
When to call a pro Stop and call a technician if you suspect a broken spring or cable, if the door is off its tracks, or if it feels extremely heavy when you try the manual release. These involve high tension and real injury risk.
The safe DIY zone is batteries, power, locks, and sensor cleaning. Anything involving springs, cables, or the door's weight belongs to a trained pro. When in doubt, a free quote costs nothing and keeps you safe.