It took a while, but eventually I figured it out. The Sri Lankan outlets were unlike any I've seen in any other country. They looked as though my Euro 2 round prongs adapter should work, however it would not fit in the socket. After unplugging everything in my room and not being able to plug it back in I began to get frustrated. The lamps and TV were plugged in as you'd expect, just leaving the upper 3rd prong empty, similar to a lot of US plugs where they have the optional ground hole. I tried a lot of things, including brute force, but nothing worked. Eventually it hit me, that maybe I should plug it in diagonally because there was another outlet in my bathroom which had 3 holes as well, but for a US style plug, and if you used the left 2 it was 110 volts, and if you used the right 2 it was 220 volts. I gave it a shot, and accidentally shorted something and shut down power in my whole section of the hotel (not the first time I've done this abroad messing around with strange power adapter configurations).