Windows 10 Feature Update 2004 appears to have broken Windows Live Mail

Thank you so much.  This solution worked perfectly for me.  The DWORD entries were already there, so I just changed the "(0)" to "(1)".

Many thanks for your feedback ClitheroeKid - its great to hear from some one who knows what they are talking about. Can I just double check a few points with you and then I hope I'll fully understand the situation.

I understand what you're saying about Microsoft stopping the sync process so we would no longer expect to see any syncing between the WLM calendar and the calendar I see when I use my browser to login to my hotmail account.

What I'm still a little bit unclear about is the "working online and globe" that I see in the bottom right hand corner of the WLM window. I've always been a bit puzzled about the function of this "icon". I don't think I fully understand what this does, and I don't think I ever have if I'm honest - it seems to conflict with the obvious meaning of the word online.

If I look at my own WLM system right now I have 'signed out' in the Options/Connection window but I see both "working online" and "working offline" appearing in the bottom right hand corner of the WLM window. If I left click on "working online" it changes to "working offline" - I can left click (or right click) on it till the cows come home but it will not change back again. However if I go back to looking at my Mail window and then back to the Calendar window after a relatively short while (perhaps several minutes) it will turn back to "working online" by itself. Whether it says working online or offline there is no change in the calendar entries (they are all blank as this is a new installation - but I do have entries in my browser based view of my hotmail calendar). I don't understand what is going n here!

You say "Make sure you are really looking at the one stored in your main local account in WLM, and not (a) the one stored online, nor (b) one stored in some other e-mail account in WLM." however I thought what you said earlier meant that I would not be able to see any online calendar using WLM since the sync service had been discontinued - am I misunderstanding what you are saying here?

You also say "You should see your calendar entries if you sign-in, using the button at the right-hand end of the ribbon. And, for the future, it may be better to use the online calendar, which will be available to you from any computer with an Internet connection, and also in a smart phone." I don't understand how I could see my "online" calendar entries if I sign in (by clicking in the Options/Connection window?) since the sync process is no longer running?

I'm sorry if I'm being a bit dense and not understanding all you have said but if you could fill me in on where I'm going wrong it would be a great help. Thanks.

Calendar

To view the Calendar, switch to the Calendar window by pressing Ctrl+2 or by clicking on the Calendar icon at the foot of the folder pane.

To add a New Event, in Windows Live Mail press Ctrl+Shift+O > Connection and then select "Stop Signing In": after doing so, you can then add a New Event.

You have several different calendars available in Windows Live Mail; one is the default calendar you see when you're not signed-in; and another is the one you see when you are signed-in (this is the calendar belonging to the Microsoft account you signed-in with).

Once upon a time, an account calendar stored locally in your computer would synchronize with the one at calendar.live.com, so you saw the same entries in Windows Live Mail and in the online calendar.

The synchronisation stopped working years ago, when the service it used was discontinued; the online calendar no longer contains the entries you add in WLM, and vice versa.

What I mean is, you have 2 calendars (more, if you have multiple accounts setup in WLM). Probably, what you are looking at is not the calendar you think it is. You might not be seeing your calendar entries, because you are looking at the wrong calendar. For example, if you have been saving your entries in the off-line calendar (stored on your computer), you will see an empty calendar if you now look at the on-line one -- because the two don't sync any more.

Make sure you are really looking at the one stored in your main local account in WLM, and not (a) the one stored online, nor (b) one stored in some other e-mail account in WLM.

You should see your calendar entries if you sign-in, using the button at the right-hand end of the ribbon. And, for the future, it may be better to use the online calendar, which will be available to you from any computer with an Internet connection, and also in a smart phone.

Beware of the button in the "ribbon" in WLM that puts you in the "work offline" state. If accidentally clicked, you become perpetually offline, with no access to any calendar entries stored in the on-line calendar.