Hello, I have recently been informed by one of my users that they are experiencing a peculiar issue in regards to their SharePoint calendar. A brief history is that we are currently using SharePoint Foundation 2013 with Outlook 2010, all of our users have calendars for their departments in SharePoint, and those calendars have been added to Outlook for their convenience. This particular user has a SharePoint alert set up on their calendar for all changes, and receives an alert immediately. After some troubleshooting, this is how my user is getting the issue they described:
User1 will create an appointment from Outlook on the SharePoint calendar that User2 has their alert set up for. User2 will receive the appropriate alert email that there has been a new event added to the calendar. User1 then receives an Outlook reminder that their event is coming up. If User1 clicks "dismiss" on that reminder, User2 will have another alert email generated hours later which informs them that the calendar event for User1 has been modified. If you view the event from SharePoint it will show a new modified time with User1's name, even though there have been no changes made. The other interesting part about the modified time is that it will not reflect when User1 clicked dismiss on the reminder, instead it will reflect the time that the SharePoint alert email was generated.
This is not a fluke issue; I've been able to recreate the scenario 100% of the time if I follow this pattern. I can also simulate it on any calendar I create or that is already existing in our environment.
I have been researching and trying to find an answer to this problem for several days now, but the only thing I have found is a post from someone else experiencing the same issue with no solution. So any feedback would be greatly appreciated. If there is more information that is needed to better assist me, please let me know.
Thank you for your time.