Adam wrote Send a screenshot of what it says. It'll be more help.

Where did you get your Windows image from? Was it direct from Microsoft?

Yes direct from windows, I just done another clean install and found that if I open windows own mail program windows defender will pop up with a threat found and the mail app will close down.

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I am currently doing a full system scan

again malware bytes comes up with nothing

How did HTML:Phish-B get on my Computer?

HTML:Phish-B can gain entry onto your computer in several ways. Some of the common methods of HTML:Phish-B infection include:

Downloads from questionable websites
Infected email attachments
External media, such as pen drive, DVD, and memory card already infected with HTML:Phish-B
Fake updates that trick you installing them
Programs posing as fake virus removal tools
Infected documents circulating on peer-to-peer (P2P) file sharing networks, torrent sites, and IRC channels

I'd recommend download a fresh install of Windows 10 from [ Register or Signin to view external links. ] and going from there making sure that you are not doing the above list.

If Windows Defender has picked it up, you're probably safe since it would have removed the issue.

Adam wrote

How did HTML:Phish-B get on my Computer?

HTML:Phish-B can gain entry onto your computer in several ways. Some of the common methods of HTML:Phish-B infection include:

Downloads from questionable websites
Infected email attachments
External media, such as pen drive, DVD, and memory card already infected with HTML:Phish-B
Fake updates that trick you installing them
Programs posing as fake virus removal tools
Infected documents circulating on peer-to-peer (P2P) file sharing networks, torrent sites, and IRC channels

I'd recommend download a fresh install of Windows 10 from [ Register or Signin to view external links. ] and going from there making sure that you are not doing the above list.

If Windows Defender has picked it up, you're probably safe since it would have removed the issue.

Would this explain as to why everytime I open up mail I get a defender notifcation coming up saying a threat has been found?

Ill do another fresh install with the link provided but it is the same place as before (checked history)

should I just clear my whole inbox?

Whey, now we're getting somewhere.

You've been sent something via your email and Windows Defender is picking it up. I'd delete the email with the attachment or as you said if you want to be over cautious, delete your whole inbox // deleted items.

At least we know it's nothing to worry about... as long as you didn't click it..

Just install windows vista it's way better no virus's or nothing on that version since it's the best.

With all the help provided it appeared to be a simple malicious email... good to be safe I guess?

Thanks guys!