SureAI

I wanted to pass of Nehrim to oblivion so I uncheck the nehrim file and I check all the thing who go with oblivion. After that I was able to play at oblivion but but the game menu, the intro screen and etc were those of nehrim. Everything of Nehrim ,except the story and the land , replaced those of oblivion. so after that I decided to uninstall Nehrim and when I came back to oblivion, it was the same thing. What can I do to have back my oblivion game