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Check if this help you: <a href="http://www.infralib.com/2015/08/how-to-add-or-remove-extensionattribute-of-an-ad-user-object/" rel="ugc">http://www.infralib.com/2015/08/how-to-add-or-remove-extensionattribute-of-an-ad-user-object/</a>
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writing to the attribute is not a problem. &nbsp; I am searching to determine the maximum length of data I can populate into the field
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I am using an application to populate Active Directory extensionAttribute12. &nbsp;How long can the string be that is written to this field
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I am using an application to populate Active Directory extensionAttribute12.  How long can the string be that is written to this field

Using extensionAttribute12

Active Directory (AD) is a Microsoft brand for identity-related capabilities. In the on-premises world, Windows Server AD provides a set of identity capabilities and services, and is hugely popular (88% of Fortune 1000 and 95% of enterprises use AD). This topic includes all things Active Directory including DNS, Group Policy, DFS, troubleshooting, ADFS, and all other topics under the Microsoft AD and identity umbrella.