What helped fix your issue? (if anything)

Run as Admin 1 4.35%
Logging in as Admin 0 0%
Disabling UAC 0 0%
Windows Updates 1 4.35%
Reinstalling IE8 0 0%
Repairing League of Legends 2 8.70%
Disabling Antivirus/Firewall 0 0%
Deleting the folder and allowing to redownload (8/8.1) 6 26.09%
Full Clean Reinstall 1 4.35%
Not fixed! :-( (Post below!) 12 52.17%
Voters: 23.