Uninstall Exchange 2013 after migration failing at step 8, language packs.

Question

Moved to 2019, uninstalling 2013, GUI stopped at phase 8, am getting this when I try to remove manually.

Performing Microsoft Exchange Server Prerequisite Check

Configuring Prerequisites COMPLETED

Configuring Microsoft Exchange Server

Preparing Setup                                                                                   COMPLETED
Language Files                                                                                    FAILED
 The following error was generated when "$error.Clear();
                $regPath='HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall';

                $PackageGUIDRegEx = "{DEDFFB[0-9a-fA-F]{2}-42EC-4E26-[0-9a-fA-F]{4}-430E86DF378C}";

                $InstallPath = (Get-ItemProperty 'HKLM:\SOFTWARE\Microsoft\ExchangeServer\v15\setup').MsiInstallPath

;

                if(test-path ($regPath))
                {
                    Write-ExchangeSetupLog -info ("Removing " +  $RoleLanguagePackType + " Language Packs.");
                    Get-ChildItem ($regPath) | foreach{
                        if($_ -match "(?<ProductCode>$PackageGUIDRegEx)") {
                            $langPackPackageCode = $matches['ProductCode'];
                            if($langPackPackageCode -ne $null -and $langPackPackageCode.Length -ne 0) {
                                Write-ExchangeSetupLog -info ("Removing package $langPackPackageCode");
                                $language = $langPackPackageCode.Substring(20,4);
                                $logFilePath = [IO.Path]::Combine($RoleLogFilePath,"Uninstall") + '.' + $language +

'.' + "Client" + "." + $RoleLogDateTime + ".msilog";
uninstall-MsiPackage -ProductCode ($langPackPackageCode) -LogFile ($logFilePath);
};
};
};
Get-Childitem -Path $InstallPath -include ".Localized.js",".Localized.min.js" -recurse | forea
ch ($) {remove-item $.fullname};
Write-ExchangeSetupLog -info "Remove Language Packs completed.";
};

    " was run: "**System.UnauthorizedAccessException: Access is denied** ---> System.ComponentModel.Win32Exception: Acce

ss is denied
--- End of inner exception stack trace ---
at System.Management.Automation.Utils.NativeDirectoryExists(String path)
at System.Management.Automation.SessionStateInternal.IsItemContainer(CmdletProvider providerInstance, String path, Cm
dletProviderContext context)".

In the log file:

[12/10/2020 01:00:09.0727] [1] The following 1 error(s) occurred during task execution:
[12/10/2020 01:00:09.0727] [1] 0. ErrorRecord: Access is denied
[12/10/2020 01:00:09.0727] [1] 0. ErrorRecord: System.UnauthorizedAccessException: Access is denied ---> System.ComponentModel.Win32Exception: Access is denied
--- End of inner exception stack trace ---
at System.Management.Automation.Utils.NativeDirectoryExists(String path)
at System.Management.Automation.SessionStateInternal.IsItemContainer(CmdletProvider providerInstance, String path, CmdletProviderContext context)
[12/10/2020 01:00:09.0743] [1] [ERROR] The following error was generated when "$error.Clear();
$regPath='HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall';
$PackageGUIDRegEx = "{DEDFFB[0-9a-fA-F]{2}-42EC-4E26-[0-9a-fA-F]{4}-430E86DF378C}";
$InstallPath = (Get-ItemProperty 'HKLM:\SOFTWARE\Microsoft\ExchangeServer\v15\setup').MsiInstallPath;
if(test-path ($regPath))
{
Write-ExchangeSetupLog -info ("Removing " + $RoleLanguagePackType + " Language Packs.");
Get-ChildItem ($regPath) | foreach{
if($_ -match "(?<ProductCode>$PackageGUIDRegEx)") {
$langPackPackageCode = $matches['ProductCode'];
if($langPackPackageCode -ne $null -and $langPackPackageCode.Length -ne 0) {
Write-ExchangeSetupLog -info ("Removing package $langPackPackageCode");
$language = $langPackPackageCode.Substring(20,4);
$logFilePath = [IO.Path]::Combine($RoleLogFilePath,"Uninstall") + '.' + $language + '.' + "Client" + "." + $RoleLogDateTime + ".msilog";
uninstall-MsiPackage -ProductCode ($langPackPackageCode) -LogFile ($logFilePath);
};
};
};
Get-Childitem -Path $InstallPath -include ".Localized.js",".Localized.min.js" -recurse | foreach ($) {remove-item $.fullname};
Write-ExchangeSetupLog -info "Remove Language Packs completed.";
};

    " was run: "System.UnauthorizedAccessException: Access is denied ---> System.ComponentModel.Win32Exception: Access is denied

--- End of inner exception stack trace ---
at System.Management.Automation.Utils.NativeDirectoryExists(String path)
at System.Management.Automation.SessionStateInternal.IsItemContainer(CmdletProvider providerInstance, String path, CmdletProviderContext context)".
[12/10/2020 01:00:09.0743] [1] [ERROR] Access is denied
[12/10/2020 01:00:09.0743] [1] [ERROR] Access is denied
[12/10/2020 01:00:09.0743] [1] [ERROR-REFERENCE] Id=LanguagePackUninstallationComponent___9a89e7313d524f298d51c24709f69125 Component=EXCHANGE14:\Current\Release\Shared\Datacenter\Setup
[12/10/2020 01:00:09.0743] [1] Setup is stopping now because of one or more critical errors.

Answer 1

In typical Microsoft nutty fashion I gave up and went to bed. This morning, in the same window I ran the same uninstall command only now it worked. I guess Exchange wasn't ready to be removed just yet. 2013 is now gone.

Answer 2

The same approach works with Exchange Server 2016 as well. In our particular case, we restarted the server, ran setup.exe /mode:uninstall again, and it worked like a charm.