The following error message is generated when opening a model in the AutoCAD integrated platform: "Internal Error: !dbobji.cpp@8749: eNotOpenForWrite"
This issue can occur for some models when using the SELECTseries 4 release. However, testing has indicated that after upgrading to a later release, the error will no longer occur. Be sure to check the Compatibility Chart to assure that the version of WaterGEMS or WaterCAD you are using will integrate with your AutoCAD version.
This can also happen when opening certain existing model files from the AutoCAD Start screen. In this case, try starting a new drawing. Once this is done, open the file by going to the "A" menu at the top or the File pulldown menu, and choosing Open.