Exact same issue but i cant get to seem to fix mine. PREASE HELP

So I am having this same problem. I reinstalled the game and did the repairs, but as soon as i press play, nothing opens up. I dont get the log in screen. What do I do?

Same issue here.

When I click on the shortcut, it won't open.
My computer recently crashed during an update and since then it won't even open.
I have uninstalled and reinstalled League and that still hasn't fixed it.
Anyone have any help?

I was playing a game and then it disconnected me from it now i cant even open my LoL while the game is on this is the second time this has hapend.Also i opended it once i was Reconnecting but it did not le me do it it told me to re start it and now it wont open

I keep on getting this message that says "rads kernel stopped working" or something along the lines. I've tried the methods here to no avail.

11-07-2011
Ok so today i figured out. What seemed to cause mine was I had done a system restore on Windows and apparently that messes up LoL. SO follo these steps to fix:

1. Uninstall LoL, Pando Media Booster, and Adobe Air.
2. Restart your computer
3. Install LoL and Adobe Air
4. Delete everything in the C:\Riot Games\League of Legends\RADS\downloads folder
5. Delete lol_air_client and lol_air_client_config_na inside C:\Riot Games\League of Legends\RADS\projects
6. Restart your computer
7. Run LoL in Administrative mode

make sure to bump this to help all those whose LoL launchers arent working.
I Just found this thread, it fixed all my problems hope it helps

worked for me too, lol is working and I can play but just take a little bit longer to start once I click on the shortcut, but still better than not being able to play