If you have the Shivering Isles expansion, I would reccomend getting the oblivion 1.2.0416 patch. You can then upgrade to the Unofficial SI patch. If you don't just go straight for the Unofficial Official Patch 3.2.
Now, I am assuming you have vista as you said you turned off the UAC. I don't have vista, but I wonder if the files are in the correct place. I would try to re-install the mod with the uac off. Just over-write any files. You don't have to delete them for this simple re-install. If that doesn't work, try getting back to us.
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Official Oblivion Patch v.1.2.0416Unofficial Official Oblivion Patch 3.2If you have any of the expansions, you should look up "unofficial official" on the nexus. It will direct you to the pages for the SI expansion, as well as the Knights of the Nine and everything else that came on that disk. Also is an expansion called Battlehorn Castle that I'm pretty sure you can only get via download from the company site. All these have patches too, but for now the only ones you really need to worry about are the shivering isles (optional. also optional is the UOP for SI) and the UOP (unofficial official patch) 3.2
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Did you by chance update to the patch provided in the Knights of the Nine? If so, a clean install of Oblivion is needed. You should install Oblivion, then Shivering Isles, then the 1.2.0416 patch. If not, just install Oblivion, then the UOP 3.2