Hi everyone. My car is a 1998 C180 Classic. It is built for Australia market and no extra options come with the car. My car key is not the mechanical one. Recently I couldn't use the interior knob and remote to open the boot lid. Today, I can't even open the boot lid with the mechanical keys - I inserted the key, twisted it and pressed the button, it still failed to open (no click sound and its relatively easy to press). When I pressed the remote and the knob in cockpit, i could hear the sound tho. I have no ideas about how to access to the boot lid from rear seat, since it has neither ski packages nor folded seats. The cushion is basically bolted on a metal plate. My bag is still inside and tonight I can't do any work because I can't take the bag out. Please help me guys.. Cheers!

 

Try giving the boot lid a couple of good bumps with one hand while the key is turned with the other hand. be sure the lid is not stuck to the rubber weatherstrip (i.e. try pulling up on the trunk lid while turning the key).
Hope this helps