I have a AST 24igb-w aircondioner. The remote was dropped last night. I put the batteries back in the remote and reset the clock. The remote does not sync with the unit. I can not swich the unit on or off. Can you help?? Please. we are expecting temp today in excess of 105 F.

In the remote there is a sensor.with that sensor the remote gets connected to the unit.but if that sensor is cracked the remote will not get communicated with unit because the sensor is cracked faulty so no signal will be sent.
you can only try opening the remote completely.
some remotes have screws, some have plastic locks and some are dye based they no locks and no screws.
if yours have screws then take a screw driver remove the screw and open the remote.if yours ave plastic locks take a thin strong knife and insert where the locks are seen.the locks are internally fitted so you will have to insert the knife in between the two parts of the remote and move the knife where the knife gets stuck there will be lock.move the knife up/down position lock will be released.there will be 6 to 8 locks.
if there is nothing like locks and screws then also take the knife and separate the remote in two parts.you will see thing line in between the two parts of the remote there you have to place the knife and separate the remote in to two half.after the remote is opened.check out internally.the parts will be slightly moved.lift the moving parts and reset it again properly and check out.if still the same problem the remote needs replacement.you can get replacement remote from local electronics hardware shop dealing in remotes.
This will help. Thanks please keep updated.please do rate the solution positively .thank you for using fixya