My 1999 subaru legacy outback (wagon) trunk won't open. I can hear the lock opening and closing but I can't get the trunk to open. Sometimes I try it like 50 times and maybe it opens...sometimes it opens every time for a month...but now we re in a stage and it won't open at all... and having a wagon that won't open is super frustrating...

no year car told. the now lost free users guide is by year.
made 1994 to present (even 1989 as legacy outback)
no country told at all
sorry cars not the same world wide.

open glove box, read the users guide? oops locked too>?
most cars sold in USA , called wagons
opening the rear gate hatch by accident driving
kids fall the ground, or cargo hits cars behind you. (so is illegall that feature)
and is never called a truck ever, in a wagon
only on sedans. a hatch or 5th door it is named.
In Europe then even call them 5 door cars.
so I am confused.
so all keys lost to the car. and can not drive it
nor open any side doors
and rear hatch is locked and valuables in cargo area to fetch, right?
I say call a locksmith
and pick the lock.
the door lock(mechanism) in the hatch internal, is accessed from the inside of the hatch open.so no why to attack it that way.

call a locksmith,

you gotta check the door switches, one of them is faulty,

bad sensor button maybe

I have a 99 Subaru Legacy Outback wagon also. I just changed my fluid & filters. There is a spin-on AND a bolt-in that's inside (you have to drop the pan).

When you try to open get a friend to lift bonnet at same time
When open spray all linkages with wd 40

the rocker switch on top of your steering column is on.

Unfortunately, you will have to remove the panel of the door, Use flathead screwdriver to pry open. It is very likely the spring fell off.

Check for a rusty handle. If you push the handle forward then try the power unlock then open the door with handle. I have been finding that the handle becomes rusty and does not return all the way when released. Therefore not allowing the locks to disengage. Hope this helps.

Usually the problem is that the handle has not returned to the fully down position, probably because it's getting old/rusty.

When this happens on my Outback I just push the handle down until I hear it engage, then pull up and the door opens.

Some people lube the handle regularly. I haven't had to yet.