Cant drag with one finger

After upgrading to Mountain Lion the option avaiable in the trackpad where you click something just by touching it was disabled. I just had to enable it and it worked perfectly.

The only problem is that I cant drag anything just by touching the track pad as I always did. Its somehow disabled because I can actually drag if and only if i physically press the lower buttons of the trackpad.

I tried erasing the cache located in libraries and tried the repair option in the recovery partition to no avail.