According to an eye witness who reported on ChessGames.com the problems were caused by the Mayor of Sofia and his sense of humour. The Mayor officially opened the event by making the first move in the Carlsen - Topalov match.
Instead of making one move, he made two, however. Both as white. He explained that this is how he and his friends did it in his childhood. They had misread the rule stating that a pawn is allowed to go two squares forward the first time it moves. Undoubtedly happy with his crowd pleasing joke, the good Mayor corrected this mistake and moved the d-pawn forward two squares as Carlsen had instructed him to.
Humour, however, is not the domain of technology. Instead of smiling the computers got utterly confused. What is this? Two white moves? Oh, and this, three? A pawn moving backwards? A fourth? A fifth? All by white? Hey, guys, how about reading a rule book? And with this the live transmission went down. Not only from the Carlsen - Topalov match, but from the two matches that had already started as well. I guess the programmers at DGT found a test case they didn't think of before. And while chess seems to be one of the easiest sports in the world to report live from, practical experience is indicating otherwise.
Anyway, the games came in a few hours later. It turned out to be a fine one by Carlsen who defeated the world's top rated player in grand fashion.
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