Hey, It seems I'm havig the same problem as a hundred other people, yet I've found no solution in other threads. I downloaded the .jar, but double clicking it gives me the error "invalid or corrupt jarfile". I tried running it manually with command prompt, but it gives me the same error. I downloaded and run jarfix, but it didn't help. I tried the .exe installer, but that gave me the error "this app can't run on your PC"

I'm running windows 8 (64 bit)

I've copy-pasted all three errors to a jpeg, though it doesn't provide you with any new information, but screenshots were asked in other topics, so I'll provide it.

Did you download this file from files.minecraftforge.net ?

 

And I see you use windows, you can download the .exe installer too.

Like I said, I already tried the .exe, it gave me the "can't run on this pc" error.

I got the files from http://files.minecraftforge.net

Please provide the md5 checksukm of the jar you're trying to run. As well as the EXACT link you used to download it.

Also try clearing your internet cache, None of the files on our server are corrupt.

Ah, there was an adf.ly prefix. removing it gave me an uncorrupted file.

interesting that shouldnt happen unless youre using some stupid download manager or some script that interfears with adfly, but, thats part of the reason we provide both links.