This browser is no longer supported.
Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support.
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(128, 8%, 22%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EA%3C/text%3E%3C/svg%3E)
Since thursday morning 12/07 06:00 we noticed a change in our shared calendars, in the .ics files to be precise.
We investigated the issue and upon inspecting the contents of the ics file, we found that except for the very last event, all END:VEVENT lines are missing, and the END:VCALENDAR is also missing. The ics definition states that the file must begin with a BEGIN:VCALENDAR and end with END:VCALENDAR and each calendar item should start with BEGIN:VEVENT and end with END:VEVENT.
We use the iCal.net NuGet package to parse the ICS file to a model, and since aforementioned date, we are getting exception on parsing the ICS.
This NuGet package has not been updated since 10/04/2021, and we had no issues before last week. So we can safely assume that the package is not the cause of this issue and that the content of the ics file has changed
Is this an intentional change in the ics file generation on the side of Microsoft Outlook?
Scheduling and managing events using Outlook.com calendar
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Hi Jerry,
I'm Diane and I'm happy to help you today.
It's a bug. It was reported to Microsoft over the weekend but I don't have a status report yet.
If you have an Microsoft 365 business account, the admin should contact support via the admin.microsoft.com portal.
Let me know how it goes, I'm here to help you further if needed.
-- Diane
Looks like a fix was just rolled out, all our subscribed ICS calendars just started showing events again and I'm seeing correct END:VEVENT and END:VCALENDAR markup in the raw files.
Thanks everyone for helping get this fixed quickly!
Our institution uses google and we are running into this issue as well, since it seems any event sent to us from Outook is missing END:VCALENDAR and thus gmail fails to fully parse the ICS file.
Discovered the same issue happening for me. No matter how many events are in the ical feed, there is only one END:VEVENT tag and it's at the end of the file. Also, there's no END:VCALENDAR at all so anything that we use the feeds for are failing validation and breaking functionality. Hopefully MS fixes this soon.
We are also experiencing the issue in our production exchange environment. However, our qa environment is not affected. I have been waiting on MS to respond to my support call. Odd thing is that our QA env is working as expected.