I recently changed my clutch and clutch fork and everything in between, but now it pops out of fourth and fifth gear everything is tight to proper torque. I have a 99 impreza outback sport with the 2.2 5 speed can anybody give me some any ideas on how to fix this problem.

Sounds to me like a bad syncronizer. First thing id check tho is fluid level since u should have drained it to drop trans. Even if u didnt some should have come out the tail shaft. If not maybe it was low to begin with. Simple stuff first.

Even before that make sure the linkage is adjusted properly and the bushings are good. If it did not do it before you replaced the clutch, it shouldn't now.

sounds like shifter bushings.....or bushings in the stay rod..... maybe its not getting into the gear enough and popping out....like going halfway in? idk check small things first. diagnosing gets pricey quick

It was just fine before I replaced everything went into gear each time, never touched the linkage just the 2 bolts holding it up to the bottom of car.

anuther comen problem on the end of the main shaft is a large 34 mm nut that holds the gears to the shaft it likes to come loose and alows the gears to move need to take off awd and tail shaft retiten the nut and should be fixed should be done before nut falls off and gets chewed up this is not a hard fix unless awd is damaged. Should check the end play of input shaft at same time