Null object Id Error

General

An error in the data structure in a drawing file will often result in Ebase displaying an error:

An error occured while accessing a drawing file.

"Null object Id"

This error means that at least one entity or property of the drawing is broken or missing something. The drawing may be able to be repaired, or the drawing or at least one part of it may need to be replaced or recreated.

The specific error message is from the program library that allows EDS programs to read DWG files and is that libary's description of the error in the drawing file structure.

There is no known reason why drawings sometimes develop this problem. It is not caused by entering incorrect data into EDS symbol attributes.

If a drawing has this error, then the process of reading the drawings fails and the EDS procedure that you are attempting to run will not complete.

Analysis and fixing

• Identify the drawing.

  If the project is being read at the time by Ebase or one of the other programs, then you should see a progress bar with the drawing name in the background when this error appears.

  If the background cache update is reading the drawing then there will be no progress bar (and the error window will be from SLicence.exe). In this case you can erase the "cache" folder and use Global Editor from Ebase to force a read of all drawings.

  If you cannot identify the drawing from a progress bar, you can instead add the drawings individually to a temporary test project until you identify the one with the error.

• Use AUDIT or RECOVER.

  Run the CAD package's AUDIT and/or RECOVER command on the drawing to attempt to fix the error.

• Identify the entity.

  If the drawing is not fixed you can attempt to isolate the drawing entity that has the error by bisecting the contents of the drawing until you are left with the broken entity.

  • Make a copy of the drawing.
  • Put the copy into a temporary Ebase project as the only drawing.
  • Erase half of the entities from the copy and test for the error.
  • If the error still occurs then repeat erasing half of the entities remaining in the drawing and re-testing.
  • If the error did not occur then the half of the entities that you erased must have contained the error. Make a new copy of the drawing and this time erase the other half of the entities, and repeat.

  NOTE: The error may be in a drawing that you have Xreffed into the EDS project drawing, e.g. a schematic drawing border or one part of a Paneldes model. If the error is from an Xref then you must bisect the Xref drawing instead.

• Erase and re-insert the entity.

  Since AUDIT or RECOVER were unable to fix the error, once you have identified the specific entity you should erase it and re-insert it.