exchange 2010 How to change preferred domain controller or specific domain controller in exchange 2010

First take a look at the current session settings. In this example Roaya-dc01.roayastore.com has been automatically selected.

[PS] C:\>Get-ADServerSettings | fl

RunspaceId                                 : 15e4d968-032b-4cd8-bc66-bf0b665c4161
DefaultGlobalCatalog                       : Roaya-dc01.roayastore.com
PreferredDomainControllerForDomain         : {}
DefaultConfigurationDomainController       : Roaya-dc01.roayastore.com
DefaultPreferredDomainControllers          : {Roaya-dc01.roayastore.com}
UserPreferredGlobalCatalog                 :
UserPreferredConfigurationDomainController :
UserPreferredDomainControllers             : {}
RecipientViewRoot                          : roayastore.com
ViewEntireForest                           : False
Identity                                   :
IsValid                                    : True

Using Set-ADServerSettings we can specify the preferred server for the current session with the -PreferredServer switch.

[PS] C:\>Set-ADServerSettings -PreferredServer Roaya-dc02.roayastore.com

Now Get-ADServerSettings shows this change has occurred.

[PS] C:\>Get-ADServerSettings | fl

RunspaceId                                 : b15cbfd9-5144-442e-bc74-c00a3216b864
DefaultGlobalCatalog                       : dc2.exchangeserverpro.local
PreferredDomainControllerForDomain         : {}
DefaultConfigurationDomainController       : Roaya-dc02.roayastore.com
DefaultPreferredDomainControllers          : {DC1.exchangeserverpro.local}
UserPreferredGlobalCatalog                 : Roaya-dc02.roayastore.com

UserPreferredConfigurationDomainController : Roaya-dc02.roayastore.com
UserPreferredDomainControllers             : {Roaya-dc02.roayastore.com}
RecipientViewRoot                          : roayastore.com

ViewEntireForest                           : False
Identity                                   :
IsValid                                    : True

IF is not working

 my be domain controller not Global catalog or doesn't have the correct permissions so make sure the the new DC is global catalog if not working

Insert exchange 2010 media   preferred domain controller and run CMD with administration permission

Run

 setup /PrepareDomain

enjoy

 Diyaa Oda