How to remove duplicates with part of name duplicated?

I list my files with a file handler and then export it to a text file which I open in PSPAD.

That gives me a file listing all the files across all my hard drives, my total computer.

Now pspad will remove all the duplicate lines.

That's fine for all duplicates on one drive because the whole filename/path is the same.

But the same file on a different drive is not seen as a duplicate because the filename begins with a different drive letter.

As in: C:\somefile and
D:\somefile

Can I get pspad to sort those duplicates out somehow?

I suppose I could somehow select all the filename beginning at column x and paste that into a different pspad doc ?

You can remove paths from the file names and export it into new PSPad document - Search dialog, regular expressions and COPY button