Hi Chris,
Are you using an Outlook 365 client? If so, what's the type of your email account?POP, IMAP or Exchange?
What specific operations did you do before this problem occurred? Have you granted the permissions of your calendar to someone else who might accidentally deleted your calendar items?
Can you see these appointments on your web mail? If you can see these appointments on your web mail, then please try creating and using a new Outlook profile via Control Panel > Mail > Show profile and see if there is any difference.
In this situation, please go to your "Deleted Items" folder and see if you can find these appointments here. You can also do mailbox search(search in All Outlook Items) and confirm if the missing items are in other Outlook folders.
Besides, it is also suggested to create a new meeting and see if it would disappear.
In addition, please right- click your calendar > Properties... > AutoArchive and see if you have set any
AutoArchive. If you do have set AutoArchive, then just go to find the PST file and your calendar appointments may be here, you can
import them back to your calendar.
Hope this can be helpful.
Regards,
Aidan Wang
Please remember to
mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact
tnsf@microsoft.com.
