Having troubles openning the signatures window in Outlook 2016 after installing the Office 365 version. Try the below commands to fix it in an elevated power shell prompt:
Set-TimeZone -Name “W. Australia Standard Time”
Get-AppxProvisionedPackage -online | where { $_.Packagename -like ‘*Office*’ } | Remove-AppxProvisionedPackage -Online
Get-AppxPackage | ? { $_.Name -like “*Office*” } | Remove-AppxPackage
Get-AppxProvisionedPackage -online | where { $_.Packagename -like ‘*Microsoft.DesktopApp*’ } | Remove-AppxProvisionedPackage -Online