We are having issues with Outlook 2016 (365) opening saved msg files. You can open the file once, but subsequent opens result in the above error message. Closing Outlook and reopening allows you to open the msg file again.
If Outlook isn't open, you can open/close the file as many times as you want without issue.
Tried opening Outlook in safe mode (outlook.exe /safe) and issue still present. Doesn't seem to be related to Com Add-in as originally suspected.
Any ideas as to what is causing this? Seems to be happening to all machines.
Win7, 8, 10 Pro with Outlook 2016 (365).