Transmission

ive been using this program for a looooong time. As of yesterday when I open any torrent with transmission I get a pop up window warning me I am opening an exectuable file etc etc

Why has this just started all of a sudden and what should I do etc?

Thanks

I have been using the client for a long time. a regular user. the only thing I have changed on my mac is now I have my torrents directed to my external hd or time capsule. Starting tonight whenever I am trying to open a torrent I get a pop up message "...to the effect I am opening an executable...