Write Protected

Hi all, I tried to download UBUNTU SERVER on an old win7 machine to try a go at doing a server.

I used balenaEtcher to write the ISO files to an external hard drive, which is now write protected.

I have tried Diskpart, regedit and numerous other softwares that assure me this will fix it (but doesn't).

When I right click on the drive and go to tools I  don'f have the option of changing the drive.