I have a casting reel only a few months old and barely used. I've caught a few fish on it and had no problems on any of my trips. After about two weeks of sitting at home, I decided to take this reel out today only to find I could not get it out of freespool. When I engage the reel line still plays out. I have tried tightening down the drag and even at maximum, the spool still plays out line freely. Does anyone have any idea what the problem might be and how I might fix it? I am pretty new to casting reels and have never opened one up before.

Do you have braid on the spool? If so, it really needs to have a couple of yards of mono on  the spool first, then the braid attached to that before winding it on. If you don't the braid will slip on the spool and appear that the reel's drag is not working.  If you have already dome that, then it must be a mechanical problem and needs fixing.

It's definitely not a braid problem. I fished the reel a few times and this is the first time the problem has occurred.

Does it have a flipping switch? I have an older cheap one that will free spool like that if the switch isn't pushed all the way one way or another. 

Knowing what type of reel it is will help to diagnose the problem.   Can you see the spool turning while the reel is engaged and pulling out line?

 

Is the release bar/button in the up position?  If it isn't, there is likely a spring that likely popped loose and the the gearing isn't re-engaging.  

If the braid is slipping on the spool you will see the line pack rotating on the spool relative to the spool, which will be stationary relative to the reel frame.

If the reel has been taken apart, or if the sideplates got loose and you had to tighten them, then the release bar for the free spool may be out of its proper position.  If this is the case take the reel apart again and experiment with the position of the release bar while the sideplates are slid into position.  

If these ideas don't work, I would take it to an expert or to the store from which it was purchased.

The release bar pops up when I try and reel.

Fixed, thanks everyone for the input.

What was the problem?