Hello Mudkipz!
Thank you for bringing this issue to the Help and Support Forum! Pressing the giant glowing orange button of "PLAY", and then nothing happens can be excruciatingly frustrating, since you are left with doing the exact opposite of what you clicked.
Typically, this problem is most often caused by a failed self-patch of the patcher. Although we are working to resolve this issue there are a few known workarounds:
The first and most common solution is to force the patcher to repatch itself. You can do this by deleting this folder:
C:\Riot Games\League of Legends\RADS\projects\lol_launcher
If you chose a custom install path, the folder may be in a different location.
Many players also fixed this problem by disabling the UAC(Windows Vista and Win7 Only)
Here is a short guide to disabling the UAC: http://www.howtogeek.com/howto/windo...windows-vista/
- Be sure to use the "Never notify me when:" setting
If you have completed these steps, and you are still not seeing the Log-in Screen, don't panic just yet! Make sure to send us a new Support Ticket* so we may work with you one-on-one until arriving at a Full Resolution!
* Keep in mind that this advice was given based upon the information provided. If you would appreciate a further one-on-one interaction to solve this issue, make sure to send us a Support Ticket! You can send one from here: https://support.leagueoflegends.com/tickets/new Also, if you could please provide a link to this forum thread in the new ticket, it would be incredibly helpful!