I’ve been on both ends of a broken transmittal. Sent one, received one. The sender always thinks they got everything. They’re usually wrong about the xref sitting three folders deep, or the font installed globally two years ago and forgot about, or the plot style that only exists on their workstation. The recipient gets orphaned xref icons and a phone call you don’t want to make.

eTransmit crawls a drawing’s dependency tree and collects every external reference, image, font, data shortcut, and plot style into a single transmittal set. Civil 3D makes this worse than plain AutoCAD because data shortcuts, survey database references, and corridor surface links all live outside the DWG. Manual collection at that point is just hoping you got everything. eTransmit actually knows.

eTransmit works on the currently open drawing. For sheet sets, open the Sheet Set Manager first and right-click the set or a subset. That packages all sheets together instead of making you repeat this process for each DWG.

Launching it

Type ETRANSMIT at the command line. Or go to Application Menu > Publish > eTransmit. The dialog opens with the file tree on the left showing everything going into the package, and the transmittal setup options on the right.

The hyphen version, -ETRANSMIT, suppresses the dialog and is scriptable. That’s the one you want for batch processing or wiring into a nightly archive job. More on that below.

Transmittal setups

The Transmittal Setups button in the dialog is where you build named configurations. Create one called something like External_Relative_2018 or Archive_Bound_Purged, set it up once, and your scripts reference it by name. You don’t want to click through the same options every time.

Options

Package type

ZIP is the right default. Self-extracting EXE sounds convenient but gets blocked by email security filters. Folder creates an uncompressed copy if you need to inspect or post-process the output.

File format

The version downgrade option. Pick DWG 2018, 2013, 2010, or 2007 and every drawing in the package gets saved to that format. DWG 2018 covers AutoCAD 2018 through 2026.

Path options

How xref paths get written in the packaged drawings. Relative is almost always correct. No-path works if everything lands in one flat folder. Keep existing paths only makes sense when the recipient has an identical directory structure, which is almost never true.

Remove AEC objects

Converts Civil 3D objects to proxy graphics or exploded AutoCAD geometry. Use this when the recipient doesn’t have Civil 3D. Without it, they get proxy warnings and uneditable objects that look fine until someone tries to click on them.

Bind external references

Embeds all xrefs directly into the DWG. Good for archival or for handing off one self-contained file. File size goes up and the modular structure disappears, so use it deliberately.

Set default plotter to none

Strips your internal plotter names from all sheets. The recipient doesn’t have your HP DesignJet 1050C on Port9_Server3 and you don’t want those names polluting their plotter list.

Purge drawings

Runs PURGE across all included DWGs before packaging. Reduces file size. Be careful with drawings that intentionally carry unused styles, blocks, or layer definitions as a template base.

Password

Optional ZIP encryption. Useful for sensitive project data. Tell the recipient the password through a different channel than the file itself.

Downgrading file format

This comes up on almost every external transmittal and people handle it manually more often than they should. The format option in the transmittal setup batches the conversion across every drawing in the package automatically.

DWG 2018 format covers product releases 2018 through 2026. DWG 2013 is the format for 2013 through 2017. A subconsultant on AutoCAD 2016 cannot open a 2018-format file. Ask what version they’re running before you create the transmittal setup, not after you’ve already sent it.

Relative paths and why they matter

Absolute paths in a transmittal are a classic mistake. When your DWG has xrefs pointing to C:\Users\YourName\Projects\ActiveProjects\ClientX\Phase2\Civil\ that path means nothing the moment it lands on someone else’s machine. Every xref shows as unresolved and the recipient has to manually reattach them, which is how errors get introduced.

Relative paths rewrite those references relative to the host DWG location. The folder structure inside the ZIP is preserved, xrefs resolve on extraction, and nothing needs to be manually reattached. Set this as the default in your transmittal setup and leave it there unless you have a specific reason to do otherwise.

Removing AEC objects

Civil 3D objects are proxy objects to anyone without the object enabler installed. Alignments, profiles, corridors, surfaces, they all look fine on screen but are dead geometry. Editing is blocked, properties are missing, and regeneration produces warnings that confuse non-Civil users into thinking the drawing is broken.

The Remove AEC Objects option exports proxy-graphic-safe versions of those objects. Depending on the version, it either explodes them to basic AutoCAD geometry (lines, arcs, polylines) or converts them to display-only proxies. Either way, the recipient gets a DWG they can open and work with as ordinary AutoCAD without needing any Autodesk vertical product installed.

This operation only affects the copy inside the transmittal package. Your working drawings are never modified. Check the output before sending anyway.

Scripting it with -ETRANSMIT

For anything beyond a handful of drawings, the GUI is too slow. -ETRANSMIT is the command you want for batch processing or scheduled archive runs.

Step 1: create and name your transmittal setup

Do this once in the GUI. Give it a name that describes what it does, something like External_Relative_2018 or Archive_Bound_Purged. That name is what scripts reference.

Step 2: write a .SCR script

Run it through accoreconsole.exe (C:\Program Files\Autodesk\AutoCAD 20xx) to process a drawing headlessly:

accoreconsole.exe is the AutoCAD Core Console. It runs AutoCAD without the GUI, executes scripts, and exits. Available since AutoCAD 2013 and the most reliable way to batch-process drawings.

PowerShell wrapper for production runs

For a real power pipeline, PowerShell can find drawings, call accoreconsole for each, and log results.

Civil 3D-specific things to know

Data shortcuts

Data shortcuts are XML references to surfaces, alignments, and corridors stored outside the DWG. eTransmit collects the shortcut XML files and their source DWGs, but the recipient needs the correct folder structure for shortcuts to resolve. If you haven’t coordinated project folder conventions with subconsultants beforehand, this is where things fall apart. Sort that out before the first transmittal, not after.

Survey databases

Survey databases live entirely outside the DWG and eTransmit doesn’t collect them automatically. If the recipient needs survey data, export figures to the DWG first, or package the SurveyDB folder manually alongside the transmittal.

LandXML

When sending Civil 3D design data to non-Civil software or to contractors who just need the geometry, export surfaces, alignments, and profiles to LandXML alongside the transmittal. It’s vendor-neutral and reads into most civil design and construction software without issue.

Read the transmittal report

Every eTransmit package generates a transmittal report, a text file listing every included file, its original path, its path in the package, and any warnings. Missing files show up here. Unresolvable xrefs show up here. Reading it takes 30 seconds. Not reading it and getting a call from the recipient because half their drawing is missing takes considerably longer.

Checklist before sending

• DWG format version matches what the recipient can open
• Path option is set to Relative
• Transmittal report reviewed for missing files
• AEC objects removed if recipient doesn’t have Civil 3D
• For sheet sets, launched from Sheet Set Manager, not from a single DWG
• For batch runs, transmittal setup created and named before scripting -ETRANSMIT
• Default plotter set to None to strip internal plotter names

Power Tip

You can just use eTransmit not just to send drawing or sheet set, but to repath to relative or a new structure, purge, convert all your files, create an archive backup and zip them, or just bind xrefs.