Free Mkv To Mp4 Converter Windows 10

Hello,
I have just installed Zorin OS yesterday after a few months of cursing at Ubuntu. I am transitioning from windows 7. Everything works so far, but I am unable to mount 2 of my HDDs. They did work in Ubuntu, so I am not sure what the issue is.
I see them in the disks app, but the edit mount options are greyed out.