The easiest way is to just grant "everyone" full control over the whole hard disk, so bye bye security and anyone/anything will never get an "access denied" error.
However, I think It's a VERY bad idea. That does the trick, but I would suggest AGAINST using it.
There is also a trick that lets you run elevated programs at startup, even with UAC enabled. First you can use this tutorial to create a shortcut to the program: Elevated Program Shortcut - Create for Standard User
Then place that shortcut under the startup folder of start menu.