Yep. Backups are extremely important - smart people always backup their files before installing any mod.
I know the pack probably installed it automatically, which isn't your fault, but that is why automatic installers should have uninstallers (like I did with Liberty City Customs)
I did backup the Models and others , But still nothing , It should have an Automatic Uninstaller but It don't , Which ruined the hole game files , I did backup the game from before , It took me long , I said its a Automatic Installer that should have Automatic Uninstaller.
Reinstall your game, don't waste too much time on trying to find other solution, Once the game files get corrupted It's hard to turn it back working without having your own backup files. You should've learned a lesson to backup your files before touching anything.
As I said up , I thought it has an Automatic Uninstaller .
Reinstalling the game is So hard for Me , I will explain again :
1.My DVD Reader is not working (Planning on a New PC) And I can't enter 2 CDs in it .
2.Trying to install it on another laptop is So hard and will take like 4 Hours , Because I have to install it Completely on the Laptop which will take 1-2 Hours because its an Old laptop which I don't use and
Overheats when I Start it and Have 2GB Ram and a Dual Processor ,
Then , I have to Move a 15GB Files
Using a 2GB Free space or more from a USB Moving Disk equipment , Even If more space , It will take a lot ...
The pain Is real...
(Welcome to Syria) 
you deleted the shaders? use the backup ones or as i already told you, reinstall the game
The ENB Shaders , I never saw a Shaders File that came In the CD....
Reinstalling is Painful , As I said Up ....
EDIT : I will try to sell my 2Laptops and Buy a New PC , I am Busy At the moment , Still trying.