The first thing I would try is to remove/unsubscribe that calendar, quit Thunderbird, start it again, then subscribe to the calendar again.

I would also double-check that the Outlook Calendar is still "Published", and make sure you are using the correct URL for it.

Problem is now fixed. I had done the steps you suggested before, but I tried them again--and this time I did one new thing also--namely, when sought the link from outlook.com, I did it logged in as me, rather than as my wife...and the URL link that was generated by outlook.com was a little different.

So using THAT link (which seemed to know that I had asked for it, rather than my wife)...seems to have done the trick. (That link also solved some missing events in the google calendar...).

This is not simply a matter of "updating" from outlook.com, I don't think, because earlier today I had asked Outlook com to "publish" a new link when logged in as the calendar's owner, namely my wife, and so the link which didn't work at all in Lightning and poorly in Google...was generated today also....My guess is that in Lightning, the link goes with my email address which Lightning also assumes...

That's all I can guess. At any rate, thanks for your help, and the problem is now RESOLVED.

Oops-Not Resolved After All.

After 24 hours, Lightning is again showing just one of the two calendars on Outlook.com that I've tried to subscribe to. Apparently, the problem has something to do with trying to see 2 different calendars on outlook.com using one email address (my hotmail address)....???Can't figure it out. Last night, I was able to see my wife's Outlook.com calendar on Lightning, but NOT mine. My resonse was to uncheck the display of wife's calendar, and try to subscribe to mine...That did not immediately produce results last night, but this morning, when re-starting Lightning, now is I can see MY outlook calendar on Lightning -- BUT cannot any longer enter a check to switch on or display my wife's calendar on OUTLOOK.com. While this strange behavior continues with Lightning, I am able to see both these Outlook.com calendars simultaneously using Google Calendar, and also using Outlook.com--both of these programs DO whos both of the Outlook.com calendars (read only on google calendar).

So my conclusion now: this is some kind of bug involving Lightning's interface to Outlook.com...

Any help would be most welcome.

If you think the e-mail address assigned to the calendar has anything to do with it, try this:

Right-click the calendar and choose "Properties". Change the E-Mail to "None".

I'm afraid the complications of your using multiple Outlook.com calendars, some shared, some not, and your using Google calendars also, and the various ways you are try to see them in Lightning, is too much for me. I'm confused.

I am unable to help further, sorry. Hopefully someone else can help.

Just tried your suggestion. Worked brilliantly--at least for now. Chose "none" for email in Lightning properties for wife's calendar. Bingo. It displayed instandly in Lightning, and all other calendars also displayed in Lightning.

I'll wait another day to check if this persists (previous fix stopped working after 24 hours). But it looks very good. 

Also, sorry if my description seems complex. I think it's not that complex. I am owner of one calendar on outlook.com...and also my wife has a calendar on outlook.com that she shares with me.

BOth of these are readily displayed in Google Calendar (desktop version), and also on my phone using Android calendar app on Samsung Galaxy 4 mini.

That's all I'm trying tos say...Just want to see them both in Lightning.

Thank very much for your help.

Thanks very much.