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Active Directory Error 0x51 occurred when trying to check the suitability of server '<servername>'. Error: 'Active directory response: The LDAP server is unavailable'. It was running the command 'Get-OwaVirtualDirectory'.

    Question

  • This issue is driving us nuts - there are no issues with Domain Controllers or AD in this environment.  The server it is citing in the error has been retired - it was gracefully dcpromo'ed down and removed from the environment.  DNS has no record of it, nor is it located anywhere else.  We are not able to log into Outlook Web App either with authentication failed errors - and I can't help but expect these 2 issues are related?  I tried hard coding the Configuration Domain Controller at the org level, as well as using the -staticdomaincontrollers and -staticglobalcatalogservers with the "Set-ExchangeServer" powershell command - no luck....  System settings of the exchange 2010 servers show they are pointing to the correct DCs - but I still get this error accompanied with long delays in rendering windows in EMC.  Extremely frustrating.....  I have an issue logged with MS now, but they aren't looking at them until Nov 9.  Has anyone seen this issue at all?  More info on the OWA config - using Form based auth, and I'm not able to perform a simple test-owaconnectivity -mailboxcredential (get-credential\username) -allowuntrustedcertificate -allowinsecurelogon - please help
    Thursday, November 05, 2009 4:05 PM

All replies

  • Hi,

    Did you try using Get-OwaVirtualDirectory with -DomainController <Fqdn> switch ... point to another DC.
    Nitin Gupta (gupnit) | MVP - Exchange | http://www.nitingupta.in/blogs
    Thursday, November 05, 2009 5:47 PM
  • Open Exchange Management Console -> Right Click Organization Configuration -> Click Modify Configuration Domain Controller -> Check Use Default Domain Controller...Problem should be fixed - if not - recycle ex services

    Rich Michael
    • Proposed as answer by Eagle 1 Saturday, December 05, 2009 4:40 PM
    Saturday, December 05, 2009 4:38 PM
  • Create a "global catalog" on the 2nd domain contoller, will fix this problem. 

    To create a new global catalog:
    1. On the domain controller where you want the new global catalog, start the Active Directory Sites and Services snap-in. To start the snap-in, click Start , point to Programs , point to Administrative Tools , and then click Active Directory Sites and Services .
    2. In the console tree, double-click Sites , and then double-click <var>sitename</var> .
    3. Double-click Servers , click your domain controller, right-click NTDS Settings , and then click Properties .
    4. On the General tab, click to select the Global catalog check box to assign the role of global catalog to this server.
    5. Restart the domain controller.
    • Proposed as answer by Dimiter Kehayov Wednesday, February 24, 2016 12:43 PM
    Wednesday, February 03, 2010 11:05 PM
  • This issue is driving us nuts - there are no issues with Domain Controllers or AD in this environment.  The server it is citing in the error has been retired - it was gracefully dcpromo'ed down and removed from the environment. 

    Have a look at this KB article, it seems to describe the issue you're experiencing: http://support.microsoft.com/default.aspx?scid=kb;en-us;2019500
    With kind regards / Met vriendelijke groet, Jetze Mellema | http://jetzemellema.blogspot.com/
    • Proposed as answer by Jetze Mellema Wednesday, April 28, 2010 8:29 AM
    Wednesday, April 28, 2010 8:29 AM
  • Thanks, you saved me much heartache.
    Tuesday, April 05, 2011 5:34 PM
  • couple of things first.
    once you install the windows 2008 r2 DC, it is advisable to move the FSMO roles from 2008 to R2.
    Is the 2008 R2 DC also a Global catalog server ?

    In the Exchange console do you see the DC (2008 r2) Listed ?

    Dinesh S.

    Monday, August 05, 2013 7:20 PM
  • Thank you. Such a simple fix, but those errors always freak me out. I always wonder if there's something bigger going on. 
    Monday, January 27, 2014 6:34 PM
  • Thanks, it helped me
    Wednesday, December 03, 2014 12:25 AM
  • the steps to Exchange 2010 , what about 2013 & 2016
    Thursday, July 13, 2017 10:49 AM