There can be  multitude number of reasons why a model does not open in AutoPIPE. Select link that closely resembles information from AutoPIPE Log file, Event Viewer, etc..

Note: see link here for general options available to fix the model

Open AutoPIPE's Log file and review the last lines of the file:

• <error> Point Read: Invalid id
• <error> FrameNodes Read: Invalid id
  

Open computer's Event Viewer, select Windows Log> Application> find recent Error event, select it> and review the General details about it:

Faulting application name: autopipe.exe, 

Faulting module name: ucrtbase.dll

Exception code: 0xc0000409

See Also

Bentley AutoPIPE has crashed

Bentley AutoPIPE