ERROR when printing multiple documents on PDFCreator printer

I always get the following error when I send multiple files (10 to 30) to the PDFCreator printer. Sometime not all the documents are printed as pdf then.

Error Report for PDFCreator v2.0.0.695

Exception:
System.UnauthorizedAccessException: Der Zugriff auf den Pfad wurde verweigert.
   bei System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
   bei System.IO.Pipes.NamedPipeServerStream.Create(String fullPipeName, PipeDirection direction, Int32 maxNumberOfServerInstances, PipeTransmissionMode transmissionMode, PipeOptions options, Int32 inBufferSize, Int32 outBufferSize, PipeAccessRights rights, SECURITY_ATTRIBUTES secAttrs)
   bei System.IO.Pipes.NamedPipeServerStream…ctor(String pipeName, PipeDirection direction, Int32 maxNumberOfServerInstances, PipeTransmissionMode transmissionMode, PipeOptions options, Int32 inBufferSize, Int32 outBufferSize, PipeSecurity pipeSecurity, HandleInheritability inheritability, PipeAccessRights additionalAccessRights)
   bei System.IO.Pipes.NamedPipeServerStream…ctor(String pipeName, PipeDirection direction, Int32 maxNumberOfServerInstances, PipeTransmissionMode transmissionMode, PipeOptions options, Int32 inBufferSize, Int32 outBufferSize, PipeSecurity pipeSecurity)
   bei pdfforge.PDFCreator.Communication.PipeServer.ServerThread()
   bei System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   bei System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   bei System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   bei System.Threading.ThreadHelper.ThreadStart()

Environment:
Microsoft Windows NT 6.1.7601 Service Pack 1