Emails stopped working on Windows 8.1 Mail

[#1]

My Windows Mail app on 8.1 has stopped working completely this morning for no apparent reason.    I haven't made any adjustment to any settings, 
I cannot send or receive any emails at all.  If I write an email, it stays in the Outbox until I delete it.    I can receive the emails on my mobile, my iPad and with Plusnet webmail.  Anyone any idea as to what has gone wrong?

[#2]

Is it giving you any error codes or messages?
Also have you checked and temporarily disabled any security software you may be using?

[#3]

There were no error codes at all.  It was working at yesterday lunchtime and then it just stopped working for no apparent reason.
Problem sorted by resetting the laptop and wiping it and doing a clean reinstall back to Windows 8.    I was able to set the mailboxes up straightaway.
However I now have a problem in that I'm unable to download Plusnet Protect, despite two phone calls to Plusnet Support.  Apparently it's been escalated to the department that deals with it.  That was 2 hours ago so not sure whether they will sort it tonight or not.

[#4]

I'm wondering if rolling back windows updates might have helped but I know a few that have been put off by Windows 10.
Still getting used to 8 myself

[#5]

All sorted now, thanks to excellent telephone assistance from Plusnet Support.