Converting to CMYK is not an option.

Hello,

I'd like to convert a file from RGB to CMYK. Normally, I can go into Assign Profile, and just select CMYK. However, in this case (actually hundreds of files), none of them have CMYK as an option. So, all the files remain in Untagged RGB, when I need them to be CMYK US Web Coated SWOP.

Here are the only choices available under Assign Profile:

Thanks for your help.