Exchange 2013 install fails on Organisation preparation Stage

Hey Guys ,

 I'm facing an issue while installing exchange 2013 on existing 2010 organisation , below are the details . I'm installing it on test bed however i'm failing at organisation preparation stage.

I do have existing exchange 2010 on ma domain

I would really appreciate your help.

Configuring Microsoft Exchange Server

    Organization Preparation                                  FAILED
     The following error was generated when "$error.Clear();
          install-RuleCollection -Name:"ClassificationDefinitions" -DomainContro
ller $RoleDomainController;
          New-ClassificationRuleCollection -InstallDefaultCollection
        " was run: "Unable to continue processing classification rule collection
 payload for decryption or further validations. Payload may contain invalid data
.".

Thanks