I use Outlook for my personal information manager (PIM), which encompasses calendar, contacts, and notes. I use AkrutoSync to sync these with my iPhone over home WiFi rather than going over the cloud. My Outlook is the Windows 10 desktop app, not part of Office 365 or some other cloud repository.
For the calendar, I think that I've mostly created appointment/meeting events on Outlook, which then propagates to the phone over AkrutoSync. This past week may have been my very first time creating an event on the phone and propagating it to Outlook. It shows up in my calendar, but when I try to open it in Outlook, I get a popup window saying "Sorry, we're having trouble opening this item".
I tried repairing the PST file, creating a test event on the phone, and propagating it to Outlook; I got the same message. I tried Windows's repair of Outlook, both quick and slow online repair, with the same result.
I was able to drag the un-openable calendar item to a folder, which showed as Test.msg, which is odd because "msg" is for email while calendar item extensions are "ics" or some other standard. When I double-click the file, I get a message "Cannot read the item". I sent the file to AkrutoSync, who said that they managed to open it in Outlook.
My Outlook is 2019, and bought as a standalone app (not part of Office 2019). However, I also tried opening the file on another laptop with Office 2013, and I got the same message about the inability to open the file. In contrast, AkrutoSync reported that they could open the file in both Outlook 2013 and 2019. Therefore, it seemed unlikely that the file is malformed. As confirmation, II also uploaded it to encryptomatic email viewer and CoolUtils mail convert; both sites parsed and displayed the content with no complaints.
It would seem that both of my specific versions of Outlook are alone in their inability to open the Test.msg file. What conditions (perhaps Windows settings, e.g., security, policy) prevent the opening of what is likely to be a validly formed *.msg file that contains a calendar item?
2022-05-23 update: I was able to open Test.msg on a 3rd system with Outlook 2013 with no problems. The only difference that I can think of between success on the 3rd system and failure on the 1st two systems is that Outlook had access to an Exchange server. I doubt that many people would be familiar with how AkrutoSync propagates a calendar item from the iPhone to Outlook on the laptop. In terms of less product-specific knowledge, however, would anyone know whether an Outlook calendar item can be created in such a way as to presume the availability of an Exchange server and to rely on its functionality? That would explain my observations across the 3 systems. The 1st 2 systems failed; each ran Outlook profiles containing only IMAP accounts in addition to a no-email account for the calendar. In contrast, the 3rd system succeeded; the Outlook profile had only a single Exchange account for both calendar and email.
2022-05-24 update: I asked someone using Outlook Desktop app as part of Office 365 to try opening Test.msg. It also fails. So that's one success out of 4 very different systems. The outstanding distinguishing feature of that one success (of which I am aware) is that the Outlook profile consists of an Exchange account.
2022-05-30 udpate: AkrutoSync confirmed that in their successful tests, the Outlook profile had only an IMAP account (no Exchange account). So the presence of an Exchange account in one of my Outlook profiles does not explain the success in opening the Test.msg container a calendar item. It must be some other condition that allows Outlook to open the file in some situations.
P.S. I don't have a personal Office 365 or Outlook.com account and want to avoid creating one. However, I did try opening the Test.msg as an email attachment by accessing my Gmail using the webmail interface. It turns out that doesn't even store the file as a single file Test.msg. It stores it as two attachments: "Test" and "noname" (no extension), where Test is much smaller than Test.msg and noname is much larger. Gmail said that it doesn't have an app associated with the files.
