mod problems on oblivion

Can anyone with a problem .I have downloaded some mods for Elder scrolls oblivion,extracted the files to the oblivion data files,but when i try to to run the files Iam told that they are either in an unknown format or damaged. Any help would be appreiciated.

What format are they zipped in? you can get the unknown format or damaged message if your attempting to extract with the wrong program, say winrar when it should be 7zip.

when Itry to run the files after unzipping them,I am told that it is an inauthentic archive.I have copy/pasted the files to the oblivion data files,but they don't show up in the data files when I run the game launcher.

You sure you haven't downloaded the mods for the wrong hardware? like xbox mod instead of PC?

I am still having problems getting meshes and textures to work on oblivion mods.Do I have to open every sub-file in the meshes and textures files ,and copy them to the oblivion data files seperately;or should I only have to copy the general mesh and texture files over. Copying them over seperately is so time consuming, i cannot see it being the correct method. Can you help?

Have you tried any other mods as the OS should not interfere if the game works.