Error while Installing the Azure AD connect 2.0.3.0 Getting Error as : Object reference not set to an instance of an object

Question

Hi

I am trying to install the latest version 2.0.3.0 of Azure AD connect on 2019 server, but getting below error.

[07:48:43.051] [ 18] [INFO ] ConfigureSyncEngineStage.StartADSyncConfiguration: Error details: System.NullReferenceException: Object reference not set to an instance of an object.
at Microsoft.Online.Deployment.OneADWizard.Runtime.Stages.ConfigureSyncEngineStage.StartADSyncConfigurationCore(Action1 UpdateProgressText) at Microsoft.Online.Deployment.OneADWizard.Runtime.Stages.ConfigureSyncEngineStage.StartADSyncConfiguration(Action1 UpdateProgressText)
[07:48:43.051] [ 18] [ERROR] ExecuteADSyncConfiguration: configuration failed. Skipping export of synchronization policy. resultStatus=Failed
[07:48:43.077] [ 18] [ERROR] PerformConfigurationPageViewModel: An error occurred while retrieving the Active Directory schema. The error was: Object reference not set to an instance of an object.
[07:48:43.077] [ 18] [ERROR] PerformConfigurationPageViewModel: Object reference not set to an instance of an object.

1. Un-Install the old 1.5.45 AADC tool from the server, Add and remove programs.
2. Removed the cloud sync account from Azure AD.
3. Removed the Programdata Azure AD connect folder
4. Removed the groups which were exist on Servers.. related to AzureSync

after 1 hour started Installing the New version 2.0.3.0 using the Active Server json file from the folder Exported-ServerConfiguration

But getting below error. Anyone faced this kind of issue/error, appreciate your help how to resolve this issue.

Answer 1

In your case, it sounds like something in the SQL installation for the ADSync database may have gone wrong. It can happen if you do not have the recent .NET framework installed, in which case you may need to run the .NET framework repair tool. Another possibility is that the installation file of SQL server may be corrupted.

Otherwise, this can also happen for one of several reasons:

• Most commonly, this error occurs due to some permission or .NET framework related issues on the underlying OS. In that case, verify that the prerequisites in this list are met.
• This can happen if the machine is unable to connect to the locally available domain controller. Please verify that the connection is working.
• There may be a firewall rule causing this error.

(*Note: This can also happen if you are not using the latest version of Azure AD Connect and need to update, but you already mentioned that you are using the latest version.)