Hi , please advise

I get this error while I'm do " save all"  to the general assembly it's parts and drawing.

Solid works version: 2013

The Error:

Save All have been unsuccessful.  Object reference not set to an instance of an object.

ADDITIONAL ERRORS

Object reference not set to an instance of an object.

ORIGINAL EXCEPTION DETAILS

com.transcendata.cadpdm.CADException: Object reference not set to an instance of an object.

            at com.transcendata.cadpdm.cs.CSOperationHandlerImpl.getAllModels(CSOperationHandlerImpl.java:4393)

            at com.transcendata.cadpdm.cs.CSAllModelsCollector.execute(CSAllModelsCollector.java:198)

            at com.transcendata.cadpdm.cs.CSAllModelsCollector.executeWithMonitor(CSAllModelsCollector.java:306)

            at com.transcendata.cadpdm.DefaultFromCADCollector.addRoots(DefaultFromCADCollector.java:414)

            at com.transcendata.cadpdm.DefaultFromCADCollector.execute(DefaultFromCADCollector.java:204)

            at com.transcendata.cadpdm.DefaultFromCADCollector.executeWithMonitor(DefaultFromCADCollector.java:277)

            at com.transcendata.cadpdm.InterruptibleOperationHelper.executeOperation(InterruptibleOperationHelper.java:272)

            at com.transcendata.cadpdm.InterruptibleOperationHelper.executeOperationWithMonitor(InterruptibleOperationHelper.java:350)

            at com.transcendata.swimsoa.Operations.checkInAll(Operations.java:1456)

            at com.transcendata.swimsoa.MainSwim\$9.execute(MainSwim.java:281)

            at com.transcendata.cadpdm.cs.CSOperations.processCIC(CSOperations.java:84)

            at com.transcendata.cadpdm.cs.CSHelper.processEvents(CSHelper.java:284)

            at com.transcendata.swimsoa.MainSwim.main(MainSwim.java:475)

Thanks

Ilan