@behnamlegolas I found this here http://answers.ea.com/t5/Command-Conquer-The-Ultimate/DirectX-Setup-Error-Cabinet-file-not-signed/td-p/236978 relating to the unsigned .cab problem. Its from the Command & Conquer forums but the steps are the same as with BF4.
These steps were posted by kl4ndri so give him XP if this helps:
1) Go to the folder you've installed Origin Games in (by default, C:\Program Files (x86)\Origin Games
2) Inside of the BF4, go to the install folder and then the DirectX folder.
3) Click on the redist folder and send it to the Recycle Bin with the Delete key. [Make sure to take a backup!]
4) Go into Origin, try to install again, and then when given the option to repair the game, do so. It will redownload all those files that just got deleted, and for me, this time they came properly signed.
5) The game should install properly.