Ok an update...
I put the file that has the footer i need outside the folder i want the word files to be changed (i put it in my desktop because it was inside the folder i wanted to work with). I run the macro again and now i get another error:

Run-time error '91:
Object variable or With block variable not set.

When i press debug i got the following line with yellow background:

With .Sections.First.Footers(wdHeaderFooterPrimary).Ran ge