ETRANSMIT command – A transmittal process that saves the current drawing and referenced drawing files to the selected drawing file format.
DWGCONVERT command – A batch convertor that resaves selected drawing files between file formats.
Instead, use any of the following methods to save multiple drawings to a different drawing file format: While the SAVEAS command can be used to save a drawing from one file format to another, it is not efficient when exchanging multiple drawings that need to be saved to a different format.
Bring the objects into the earlier release with the XREF or INSERT command.
Open the drawing file and re-save it to the earlier drawing file format with the SAVEAS command.
Use the WBLOCK command to export the selected objects to a separate drawing file.
If you need objects to be made available in an earlier release, as a workaround, do the following: You cannot copy and paste drawing objects between releases that use different native drawing file formats, such as AutoCAD 2012 and AutoCAD 2016.
COPYCLIP – Selected drawing objects are copied to a drawing file that is saved in the native drawing file format.
REFEDIT – Drawing files edited with the command need to be opened and re-saved to an earlier file format as needed.
WBLOCK – Drawing files created with the command need to be opened and re-saved to an earlier file format as needed.
Setting the default file format does not affect the following commands: Selecting a file format from the Save As drop-down list affects the following commands: The option to set the default file format can be found on the Open and Save tab of the Options dialog box under the File Save section. When working in an office that uses multiple AutoCAD-based product releases, you can set the default file format to use when saving to a file.