Fresh install Outlook x64 will not setup Office 365 profile?

Problem is Outlook refusing to install an Offie 365 account on a fresh Office x64 install... 

• New computer. Fresh Win10 x64 Pro. 
• PCMover (remember: recommended by MS) used to move user data over from previous Win10 x64 machine. 
• Fresh install full Office 365 x64 apps. 
• Outlook cannot open user profile. "cannot start outlook... set of folders cannot be opened"
• All other Office apps working fine.  Onedrive authenticating and sync'ing fine. 
• Repair Office. 
• Same. 
• Delete all Outlook profiles. 
• Repair Office again.  All apps appear to reinstall fine. 
• Open Outlook.  Prompted for user account.  Enter Office 365 details. 
• "Something went wrong and Outlook could not setup your account. Please try again. "
• Repeat various steps above. 
• Same each time. 

So we can't get the Office 365 account to setup on this machine at all. 

The Mail Profiles app shows up as "Mail (Microsoft Outlook 2016)" - could there be a remnant problem from the moved-data from the 32-bit install on the last machine?  If so how can we clear this so we get a clean slate? 

If not that... any other suggestions?   TIA.