My version 10 no longer synchronises with my Outlook Calendar

It has been working for for a long time now it doesn’t recognise Outlook Calendar? Other email apps do. Right now I’m using emClient for emails but have to use Calendar One on my Windows 10 desktop for my Calendar.
I have checked the air sync settings (I am aware of the Microsoft security changes) and have tried the fix within emClient. I have just now uninstalled then reinstalled emClient (I kept the database, so maybe not a clean reinstal for this problem?). I have done a full virus check. Any suggestions? thanks.

My Calendar stopped working (I’m using version 10), I tried everything I read online (I am not a geek) and nothing worked.

This is how I got it working. (accidentally by fiddling around)

I logged onto my Microsoft Account, I left it open and logged on, I have no idea if this was part of my fix.

I went in to Windows Defender and added emClient to the list of apps allowed to go through the firewall (it wasn’t on the already prepared list, I had to add by browsing for the eMclient exe file (I am using Windows 10)

I then (as I had done many times before as recommended on the www, but it didn’t work before) went into emclient Calendar, right clicked on my account name above the Calendar label and then clicked Repair then OK. …. as before the Refresh at the top left starts whirling around, but this time it did it for not seconds, but about 3 minutes and brought in all my multi years worth of Calendar appointments etc. (having reinstalled emclient a few times which made no difference and took time – I was mega happy)

I have tested the Calendar both ways between my phone and other apps, and it works! : - )

I am no geek and don’t know what part of the above made the difference, if anyone here knows please let me / others know. I have been following all the advice from emclient and other places online and nothing worked. My email and contacts worked, but the AirSync part that operates the Calendar wasn’t working ??? (after the above edits, it did)

Just thought I would share in case this is helpful to others.

Have I done anything that could cause damage?