In an official update, NovaLogic REMOVED claymores and satchels from the game, because of a problem with people spamming them in multiplayer games and it would cause horrible server lag. You can still select them as secondary weapons, but they just VANISH when you try to set them. They do not appear on the ground and they cannot be detonated because they NO LONGER EXIST as objects in the game.

For multiplayer, the solution is simple: DO NOT select the claymore or satchel as your secondary, just use grenades or the anti-tank rocket to blow something/someone up.

However, a few single player missions still require you to use these explosives to blow up certain objectives. In these instances, grenades will destroy the object but DO NOT always trigger the "objective complete" flag, meaning if you use a grenade you can never clear the mission. Instead, use the anti-tank rocket (obey the LAW!!) to do the job. The explosion sound will probably get stuck in a broken loop, but you should still be able to continue and complete the mission to unlock the next one in the campaign. Additionally, it seems that you must be standing VERY CLOSE to the target for this to work, roughly the same distance you would be if you were placing a satchel instead of using a rocket. In the third Peru mission when you go into the house to destroy the box of drugs, notice when you are close enough the box will LIGHT UP, if you back too far away it will be in shadow. Shoot it with the LAW when it is lit up.