I tried to have a texture pack and a shader running at the same time. it crashed immediately. I have since not been able to get the game up and running, even though I have reinstalled the game many times

Put the summary of the bug you're having here

What I expected to happen was...:
it wooked

What actually happened was...:
it crashed and can no longer be played

Steps to Reproduce:
1. download a tekstur pack
2. ... get optifine working
3. ... download a shader
4.... hav it running at the same time and it vil crash