Email accounts no longer function in Windows 10 Mail app

Thanks, guys, I'll have a think about it. In the meantime I have Thunderbird and a fully functioning Mail app on my other computer.

There has been a development on my problem with Mail app.

To recap, I have five accounts on my Mail app: outlook.com, gmail.com, ymail.com and two mail.com accounts. A little while ago I found that all the accounts apart from the outlook.com one had stopped working. Uninstalling and reinstalling the app didn't help . The four accounts were rather odd because they didn't show up in Registry, nor did they appear in Email and app accounts in Settings. As an experiment, I tried adding another gmail account in the Mail app hoping this would override the inert gmail account. Unfortunately, it didn't and all I'd done was to create two gmail accounts that didn't work.

Now, as another experiment, I thought I'd try adding another gmail account in Email and app accounts. I added the account successfully and logged on to the Mail app expecting to see three gmail accounts. In fact there was now just the one, and it was functioning normally! Not only that, but the two non-functioning mail.com accounts had disappeared, though the ymail account was still there and not functioning. I went back to Email and app accounts and added the ymail account. When I went back to the Mail app I found I now had two ymail accounts, only one of which was functioning.

I went back to Email and app accounts one more time and added the two mail.com accounts. When I went back to the Mail app, these were there and functioning.

Apart from the one ymail.com account, then, my Mail app seems to be working OK, but I thought I'd add this bit of information in case it's of any use to anyone.