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mmw_it's avatar
mmw_it
Copper Contributor
Sep 02, 2019

Azure AD Connect - Synchronization Service Installation fails

Hello everyone, we have a problem installing azure ad connect on a windows server 2019. when installing the syncronization service an error occurs. this is a first time installation on a brand new s...
Azure Active Directory (AAD)
rosaliod's avatar
rosaliod
Brass Contributor
Sep 10, 2019

mmw_it Sounds like your issue might be due to connectivity to a DC in your network. 

 

System.DirectoryServices.AccountManagement.PrincipalServerDownException: The server was unable to connect. ---> System.DirectoryServices.Protocols.LdapException: The LDAP server is not available.

 

Is ADDS installed on this server?

Was the server promoted to a DC?

 

Installing Azure AD Connect on a Domain Controller is not recommended due to security practices and more restrictive settings that can prevent Azure AD Connect from installing correctly.

 

I suggest going through these prerequisites. 

https://docs.microsoft.com/en-us/azure/active-directory/hybrid/how-to-connect-install-prerequisites

  • mmw_it's avatar
    mmw_it
    Copper Contributor
    Sep 12, 2019

    rosaliodYes, ADDS is installed on this server and yes, the server was promoted to a DC. This may not be recommended, but it is the most standard case in small businesses (in our case 50 users)?! We have not found and heard anything that others have problems with. Quite the reverse!

    The LDAP server is online (checked via telnet localhost / server ip 389 or 636). Naming context is like LDAP://COMPUTERNAME.ad.contoso.com/....

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