how to remove stubben files

Hi to all,

I have a problem. I downloaded a OS but my os burner did not recognize the file so I draged and dropped sed files into a separate file then the burner copyed them but now I can only delete half the files I am left with two files 1 called "boot" the other is "freenas_.". When I try to delete the files I get "This file is no longer located in C:\Freenas. Verify the items location and try again".

How can I remove these files plz.

Big ty and all the dest Vamp