I do not know what is the exact location of that file. I am searching for the OLM file in Mac system but I am not able to find that.

Under SideBar, clear the checkbox of the Hide On My Computer folders: If this doesn't work, it's suggested to try creating a new folder under the On My Computer folder. The user can easily find mac Outlook 2016 archive location & create OLM file.

On the Outlook Menu, click the Preferences button, choose General under Personal Settings. Changing the location or using a mail identity that is located on an external hard disk or a network is not supported. Please follow the steps below and see if the local folders can show in Outlook: 1. Like Microsoft Entourage for Mac 2008, Outlook 2016 for Mac and Outlook for Mac 2011 are intended to be purely locally cached mail clients. ~/Documents/Microsoft User Data/Office 2011 Identities Outlook for Mac 2011 caches your mail items in an identity in your home folder at the following location: ~/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles Outlook 2016 for Mac caches your mail items in a profile in your home folder at the following location: Additionally, using a mail identity or profile that is located on an external hard disk or on a network is not supported in either version of Outlook for Mac. We do not recommend that you change the default location of your Profile folder for Microsoft Outlook 2016 for Mac, or your Identity folder for Microsoft Outlook for Mac 2011 to an external hard disk or to a network.

Outlook for mac 2016 archive location