my game crashed when i was trying to launch it

what i thought was going to happen when i tried to launch minecraft was that it was just going to load up and take my to the main menu

what happened was when i tried to launch the game (minecraft) the screen went white and at the top it says "missingtex"

what i did to cause this
1. i tried to add a texture pack mod
2. i launched the game (minecraft)
3. the text was all messy so i tried to fix it
4. then accidentally deleted something
5. then tried to launch minecraft again and the "missingtex" screen popped up and the game crashed