Turn off Tea-Timer. To be honest I never use Tea-Timer and will never advise anyone to use it. It slows down the PC and doesn't offer enough protection to bother with.
Try cleaning your temp files and then try to download and install it again.
1) Click Start, Programs (or All Programs), Accessories, System Tools, Disk Cleanup
2) Choose the correct drive usually C:\
3) Check the boxes in the list and delete the files