Just been reading about this issue this morning (private torrent site so cant give link) and it looks like one of the latest MS security updates has messed it up
There seems to be 2 possible solutions
Remove the program from the firewall and then re add it back with access
or
if its uTorrrent then it might need a re install to allow it through the firewall
but it seems firewall related, so check there and see what it says for the program