Windows 7: Song Details Missing

As shown in the pic below on the left; when I go to certain folders w/songs in it, not all the details are listed; but these same details ARE listed when I bring the same songs into iTunes. I can edit all info when using iTunes, but when R-Clicking a song w/missing info then selecting Properties>Details & try to enter the info I want, nothing happens, I cannot enter ANY info.

I checked & I do have FULL permisions on these files, but I just cannot input info. I also tried R-Clicking>Properties>Details & Removing Properties & Personal Info, but I get the error message on the right.

Anyone here know what's going on & if/how I can fix this?