I recently noticed that nearly 1,000+ contacts disappeared from my outlook. MS tech support updated the Office 365, as it appeared that my applications were 2016 and could not be updated. After the update, we were still not able to recover the contacts and I do not know what might have happened to the contacts. The only thing I know is that no one else has access to my computer and I did not knowingly delete such a large number of contacts. I would like to find out what happened and how to avoid it.