WordPress has set up an archive page for this.
If you run into trouble, your best bet is to find your current version and download a fresh copy.
I found it easier to just simply overwrite the files using FTP from the clean version

WordPress has set up an archive page for this.
If you run into trouble, your best bet is to find your current version and download a fresh copy.
I found it easier to just simply overwrite the files using FTP from the clean version