Wont let me install ... :/

Wtf is going on? I d/l the 1gig file then go to install and i jus get this. The blue bar occasionally moves as if its still installing but it doesnt do jack. I check the folder i saved it to and theres jus a file there thats 3.99gb big called Data1.cab. After time i jus clicked the X and decided to try again, and again, and again... same thing happened. Then i tried checking the box underneath where you choose wot dir to save to (dunmo wot it is. When i click "??" i get an error saying "Runtime error 204 at 0000549C". I think i figured that "??" just be cancel "?? ??" is for About and "????" is to continue... Please help if ya can..