Issue Description

After e-mail provider migration, Outlook desktop app for Windows does not receive new e-mails. The user can view their new mail in OWA ( but the desktop client will not connect to the new e-mail provider such as Office 365. No error message is generated by the issue, but the user may be directed to Google Mail / G-Suite if they attempt to re-create their e-mail account or Mail Profile to resolve the problem.

Applies To

  • E-mail in Exchange Online / Microsoft 365
  • Outlook 2016 (16.0) or Newer
  • Windows OS

Steps to Reproduce

Users may experience this problem if they have previously installed Google Sync or other tools which are designed to connect Microsoft Outlook to Google Mail.
To reproduce the problem, the users must transition from G-Suite/G-Mail to another e-mail provider that uses Auto-discover, such as Microsoft 365 or a hosted Exchange service such as Intermedia.
While there is little official online documentation pointing directly to a link between G-Suite/Gmail and this specific problem, our migration support technicians have identified that the issue occurs most frequently with users of Outlook who previously used Google Sync / G-Sync.

Cause / Technical Explanation

This issue occurs because the sync application installed on the user's computer has made changes to the registry that affect how Outlook will handle Auto-discover. Auto-discover is the primary means by which Outlook determines the location of the mail server for a given account.
In these cases, Google Sync or other tools may have reconfigured Outlook to use a locally stored copy of the Autodiscover.xml file, and to prefer the local copy over information gained from DNS records. Thus, the cut-over of MX and Autodiscover DNS records which normally directs a user to the new e-mail service, such as Office 365, does not have any effect.


Note that removing / uninstalling G-Sync and/or removing the user's Mail Profile are not sufficient to resolve this issue. However, failure to uninstall G-Sync after migration away from G-Mail or G-Suite may cause its own issues similar to the one described here.
If you are unable to download the above file, use the code provided below, or please contact Liquid Mercury Solutions Cloud Support for assistance.

On the PC, copy the following text/code into a text file. Rename it as "Fix-OutlookGSyncRegistry.ps1", then run the script in PowerShell.
WARNING: The following code may make changes to the registry and should be used at your own risk.
Write-Host "====================================="
Write-Host " Test-OutlookGSyncRegistry.ps1       "
Write-Host " Version 1.0                         "
Write-Host " Copyright(c) 2020 Liquid Mercury Solutions. All Rights Reserved."
Write-Host "====================================="
Write-Host "This script will check for changes made by Google Sync that can prevent "
Write-Host "Outlook from correctly refreshing Autodiscover.xml after a cut-over from "
Write-Host "G-Mail/G-Suite to Microsoft 365 or other Exchange host."
Write-Host "This script makes changes to the registry. Use at your own risk."
Write-Host "Use: Fix-OutlookGSyncRegistry"
Function Test-RegistryValue() {param([string]$KeyPath, [string]$ValueName) Return (Get-Item $KeyPath -EA Ignore).Property -contains $ValueName }
Function Fix-OutlookGSyncRegistry() {
  Write-Host "Checking to make sure registry test function works..."
  If (-not (Test-RegistryValue -KeyPath 'HKCU:\SOFTWARE\Microsoft\Office\16.0\Outlook' -ValueName "OutlookName")) {
    Write-Warning "OutlookName value not found. Test-RegistryValue may not be working or Outlook is not installed on this machine."
    Write-Host "Nothing left to do."
  } Else {
    Write-Host "OutlookName value found. Assumed to be working OK"
    $keyPath = 'HKCU:\SOFTWARE\Microsoft\Office\16.0\Outlook\AutoDiscover'
    $propertyNames = @("PreferLocalXML","ExcludeHttpsAutodiscoverRedirect","ExcludeHttpsDomain")
    $propertyNames | % {
      $propertyName = $_
      Write-Host "Checking for $propertyName..."
      $found = Test-RegistryValue -KeyPath $keyPath -ValueName $propertyName
      If (-not $found) {
        Write-Host -ForegroundColor Green "Check PASSED. $propertyName does not exist in key $keyPath."
      } Else {
        Write-Warning "$propertyName found in key $keyPath. Checking value; should be 0."
        $value = (Get-ItemProperty $keyPath -EA Ignore).PsObject.Properties[$propertyName].Value
        Write-Host "Current value is $value."
        If ($value -eq 0 -or $value -eq '0') {
          Write-Host -ForegroundColor Green "No changes needed for property $propertyName."
        } Else {
          Write-Host -ForegroundColor Cyan "Setting $propertyName value to zero."
          Set-ItemProperty -Path $keyPath -Name $propertyName -Value 0
          $value = (Get-ItemProperty $keyPath -EA Ignore).PsObject.Properties[$propertyName].Value
          If ($value -ne 0 -and $value -ne '0') {
            Write-Warning "Failed to set registry property to zero."
          } Else {
    Write-Warning "Remember to restart Outlook for the registry changes applied will have no effect."


As a workaround, you may check and/or make the require registry changes manually.

  1. Open RegEdit.
  2. Navigate to Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\AutoDiscover
  3. Ensure that the keys "PreferLocalXML", "ExcludeHttpsAutodiscoverRedirect", and "ExcludeHttpsDomain" either do not exist or have a value of 0 (zero).

More Info

Liquid Mercury Solutions Internal Links

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