Hello Vinay P K
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1. Based on the Error message it seems like you have provided an error message related to external active directory preparation.
2.The error message indicates that the Active Directory user account 'domain\hcia' is ineligible to be used as a deployment user because the user is missing the Generic All permission to the organizational unit
3.Ensure that the ActiveDirectory user account 'domain\hcia' has the GenericAll permission to the organizational unit.
I. Log in to the Active Directory Domain Services (AD DS) domain controller as a domain administrator.
II. Open the Active Directory Users and Computers snap-in.
III. Navigate to the organizational unit that you want to grant the GenericAll permission to.
IV. Right-click on the organizational unit and select "Delegate Control".
V. In the Delegation of Control Wizard, click "Next" to proceed.
VI. Click "Add" to add the user account 'domain\hcia'.
VII. Select "Create a custom task to delegate" and click "Next".
VIII. Select "Only the following objects in the folder" and check the box next to "Organizational Unit".
IX. Check the box next to "Create selected objects in this folder" and "Delete selected objects in this folder".
X. Check the box next to "Read all properties" and "Write all properties".
XI. Check the box next to "Read permissions" and "Write permissions".
XII. Check the box next to "Modify the membership of a group" and "Modify the membership of a built-in group".
XIII. Click "Next" to proceed.
XIV. Click "Finish" to complete the delegation of control.
4.Verify that the specified organizational unit exists and contains the proper OUs.
I. Log in to the Active Directory Domain Services (AD DS) domain controller as a domain administrator.
II. Open the Active Directory Users and Computers snap-in.
III. Navigate to the parent organizational unit that should contain the specified organizational unit.
IV. Verify that the specified organizational unit exists and is listed under the parent organizational unit.
V. Right-click on the specified organizational unit and select "Properties".
VI. Click on the "Object" tab and verify that the object type is "organizational Unit".
VII. Click on the "Managed By" tab and verify that the managed by field is set correctly.
VIII. Click on the "Members" tab and verify that the proper OUs are listed as members of the organizational unit.
IX. If the specified organizational unit does not exist or does not contain the proper OUs, create or modify it accordingly
5.Re-run the validation process to confirm that the issue has been resolved.
Hope this helps you
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