ID:300000 SignalTap II File creation was <successful, NOT successful>

CAUSE: You attempted to create a SignalTap II File (.stp) from a design instance. As a result, the SignalTap II Logic Analyzer performed the following action:
  • Created the STP File either successfully or unsuccessfully.
The message text indicates which action occurred.
ACTION: Click OK to close the message dialog box, and then perform one of the following actions:
  • If STP File creation was successful, no action is required.
  • If STP File creation was unsuccessful, you can locate the sources of error and/or warning messages in the Messages window. Make sure the SignalTap II design instance was created with the MegaWizard Plug-In Manager , and that the design instance was not changed outside the MegaWizard Plug-In Manager. To avoid receiving this message in the future, Altera recommends using the MegaWizard Plug-In Manager to edit SignalTap II design instances, rather than editing the design file manually.