When I try to add a mod to Oblivion mod manager I get the message: Cannot open 'C\Users\Owner\Desktop\Custom_Race_Fix-1815.rar' Unsupported file type. It dose this with all mods and I have no Idea how to fix this, what am I doing wrong?
You cannot extract any archive with the extensions "7z, ace, arj, rar, zip" (there is probably more of them) in http://tesnexus.com/downloads/file.php?id=2097 (instead use http://www.rarlabs.com/), because the only extension that you can use in http://tesnexus.com/downloads/file.php?id=32277 is the http://tesivpositive.animolious.com/?page=omod_installation.
Just press the button "Load" and browse for the omod you want to be visible in OBMM for a later mod installation, but you can extract an archive which has a compressed omod with it to the related mod folder for OBMM (
\Bethesda Softworks\Oblivion\obmm\mods).