Everything Tekkit removed from Tekkit, Help!!!

[thehappyguy]

I tried to get voltz, it said update failed, i did'nt think this would affect anything else, but when i logged on to my tekkit world the walls of my house had gone, I did'nt understand why,so i looked around, my walls were made of marble. I then noticed that NEI had gone, then i realsised that everything in my inventory was vanilla. Could anybody explain why this has happened and how i fix it? I have tried logging on and off, and looking on different worlds.

I probobly should have put this on the bug boards...