Outlook calendar 'changes' appointment into a meeting after editing.

Following is a recap of Calendar issue and workaround to use until it is fixed:  

CALENDAR PROBLEM

Calendar functionality has become a problem for users of Outlook.com accounts.  Appointments created for Outlook.com accounts using Outlook for Desktop become Meetings when viewed using Outlook for iOS, Outlook for Web, and Apple’s iOS Calendar App.  The converted Meetings cannot be edited except when using Outlook for Desktop. The problem may be caused by synching of Outlook for Desktop with user’s Outlook.com account. Until this problem is permanently fixed, a temporary workaround is to stop using Outlook For Desktop to create new Appointments (instead, use Outlook for iOS, Outlook for Web, or native calendar app on your smartphone). For existing Appointments, export your Calendar into an iCal file (and then delete the Calendar from Outlook) and next import the iCal file into Outlook.com using Outlook for Web. See links below for details on how to save and then import a Calendar.

WORKAROUND FOR EXISTING APPOINTMENTS

Step 1 - Save Calendar as an iCal File 

https://support.office.com/en-us/article/Export-an-Outlook-calendar-to-Google-Calendar-662fa3bb-0794-4b18-add8-9968b665f4e6

Step 2 - Delete the Calendar 

https://support.office.com/en-us/article/Delete-a-calendar-9BA1364C-BDB0-41BE-8F66-EAF96698D021

Step 3 - Import the Calendar into Outlook.com 

https://support.office.com/en-us/article/Import-or-subscribe-to-a-calendar-in-Outlook-com-cff1429c-5af6-41ec-a5b4-74f2c278e98c

AJ, Thanks for suggesting use Windows Calendar App to create Appointments (instead of Outlook Desktop App) with Outlook.com accounts. I tested by creating an Appointment with Windows Calendar and was able to view/edit it using Outlook for Desktop, Outlook for iOS, Outlook for Web, Apple Calendar App, etc.  I will use Windows Calendar App as a workaround until Outlook Desktop App is fixed.

AJ, Thanks for suggesting use Windows Calendar App to create Appointments (instead of Outlook Desktop App) with Outlook.com accounts. I tested by creating an Appointment with Windows Calendar and was able to view/edit it using Outlook for Desktop, Outlook for iOS, Outlook for Web, Apple Calendar App, etc.  I will use Windows Calendar App as a workaround until Outlook Desktop App is fixed. 

MG, I'm glad the workaround is working for you. All seems ok so far, I haven't re-installed Office yet as can find nothing anywhere to say that this would work. Windows Calendar seems to play nicely with outlook.com and the phone apps. It's Office Outlook where the problem lies ... I hope your above reply to Barry triggers a response and I'll keep an eye on this thread and nudge again shortly.

I use Outlook on my PC and have 365 Account which provides exchange facility.  I have been communicating with Outlook App (for IOS) customer services since mid April on this.  During this time I have found out -

1 - If I create a new item>Appointment whilst in mail and have my Gmail account highlighted, then I can create an appointment that remains an appointment (and can be edited) on the Outlook for IOS App

2.  - If I create the Appointment first in Outlook for IOS App, I can then edit, change & copy within Outlook on the PC and all appointment so manipulated remain editable in the Outlook for IOS App (even the copied ones!)

3 - If I create a  meeting using the standard method of clicking within the calendar on PC outlook and send this to one of my other email accounts as a participant, it become an editable appointment with Outlook for IOS APP - i.e the exact opposite of what occurs with an appointment creation with Outlook PC.

It would appear that in transferring between Outlook PC / Exchange / Outlook for IOS App the meetings & non-meetings appointments are being transposed?

Are you still seeing the issue today?  I was able to repro it yesterday by creating appointments on my Outlook.com calendar in Outlook 2016 and then trying to edit them in Outlook.com.  When I would try to edit from Outlook.com they would show Send rather than Save.  Today they are correctly showing Save and that is using either Beta or Production UI.  This seemed to be a service side issue because I could repro with old versions of Outlook too.