Error while creating a workflow for PurchaseOrder !!

Hi all,

I have a strange error when i wante create new Workflow  of  purchaseOrder  " An unexpected erroroccurredwhen openingthe workflow.To solve the problem, checkthe event logon the serverandAOScontact your system administrator." , I follow  the trace of this error , i found this code :

try

{

workflowConfiguration = Microsoft.Dynamics.AX.Framework.Workflow.Model.WorkflowModel::Create(versionTable.ConfigurationId, curext(),domainUser);

}

catch

(Exception::CLRError)

{

throw error("@SYS327400");  // this  is the label wiche contain the message error  !!!

}

Plz  , Can some One help me.

Thanks

Taoufiq