Oh No! The Save that Disappeared

Everyone has a save reflex. <Ctrl>-S, a glance at the title bar, and get back to work. It’s like a lock turning . . . and most of the time it is!

This Just Tell Jo episode is about the other times. In August 2025, a drafter in the AutoCAD LT forum spent 16 hours on a revision, exported a PDF for the client, and watched it open with 90% of the drawing gone. Model space matched the PDF. This March, in the main AutoCAD forum, a user opened a project roughly 70% finished, about 20 hours in, and found it had rolled back several days. Unfortunately, the BAK file was just as old and there were no Autosave files even though they had been saving regularly.

Both users believed they could get back to one of their previous saves.

Image source: Planetz/stock.adobe.com, AI-generated.  

What the Field Says

The forum regulars started by asking where the file lives. In the March thread, a long-time responder opened with a single line: "Where exactly do you store your DWG files please?" The follow-up question was whether IT backed up the PC, or an app did. An Autodesk staffer pointed to the Previous Versions tab in Windows, which only helps if someone switched it on ahead of time. The thread ends without reporting back with whether or not anyone had.

The August thread runs the same route. A responder asked whether the drawings sat on a local drive, a network drive, a shared cloud drive, or a USB stick. The files sat in the Documents folder, syncing to a cloud service every 15 minutes. That sync became the leading suspect. One responder asked what happens when a sync starts when a drawing is still open. Another suggested keeping the synced folder separate from the working folder altogether. Then, the drafter went looking for the BAK file that should have been sitting next to the drawing but it wasn't there.

Software rules. The software’s rules add to some of the confusion. According to Autodesk’s documentation, the Autosave timer resets every time you save, so a diligent saver may never produce an Autosave file at all. Autosave files are also deleted when a drawing closes normally because they exist for crashes. They are not there for the day you closed the file and the work disappeared with it. In a thread from summer 2025, a Civil 3D user who saved every 10 to 15 minutes lost a drawing to a crash. The advice from a veteran was to go looking for whichever BAK or autosave file wasn’t damaged.

Cloud connectors add another layer. In July 2025, an admin in the BIM 360 support forum described a rule they’d given their team: after every action, wait for the sync icon to clear before doing anything else. The problem was that it slowed people down. The admin’s reasoning was short: “Losing work is even worse, so this is how it is.” Some applications create and delete temporary files mid-save, and that was tripping the connector into errors. When someone ignored the rule, the admin went to that person’s PC, copied the project out, reset the connector, and copied the file back. A second firm in the same thread said the warnings came so often that people learned to click past them. Unfortunately, the non-synced changes piled up until the cloud copy no longer matched the local one.

Storage. The same thing happens when the storage changes. In June 2025, a user in the AutoCAD forum explained that IT had moved all the firm’s project files into a cloud document library. Since then, the familiar warning that a drawing was already open stopped appearing. Two people could now edit the same DWG at once, and each save left a duplicate behind. A veteran responder’s answer was short: there was no fix, because the integration didn’t exist yet. Another responder described the workaround they use: copy the drawing to a working folder, leave a placeholder marked “-WIP” where it used to be, and move the edited file back when finished. The original poster said the firm was seriously considering it.

Manufacturing isn’t spared. In June 2024, a SOLIDWORKS user on a reseller’s community forum described assemblies losing their part references when opened from a synced company cloud library. Nobody else at the company had seen it. A reseller support tech’s advice was to move the files into a dedicated data management system (the reseller sells these products). A second user in the thread said that when IT fixed a sync problem for them, the same reference errors spread across a large share of their assemblies.

Sometimes the file was simply deleted. In a Revit forum thread this year, a user removed a project and its backups, emptied the Recycle Bin, ran recovery software, and still couldn’t open what came back. One reply offered a different place to look: a local copy on a colleague’s machine.

Where the Field Disagrees

The CAD field doesn’t agree on whether sync counts as a backup. The August drafter had used an external hard drive before moving to cloud sync, and was candid about why: “I often forgot to do so and let a month or two go by.” Sync fixed that forgetfulness. The drafter didn’t think it caused the loss either, having worked the same way for 10 to 15 years without trouble. The responders weren’t persuaded. They pointed out that the drafting software can’t erase a drawing's contents on its own. They also noted that a sync tool writing to an open file is a plausible culprit.

In the connector thread, one responder noted that plenty of people use the tool every day without a problem. The two firms posting had seen otherwise.

There’s also a discussion over who owns the problem. The March answers assumed an IT department had configured something. The August drafter works alone without a separate IT department.

Jo Suggests. . . 

"Save" might not be the end of your work. A save tells you the software wrote something, but it doesn't tell you where, whether a sync tool is about to rewrite it, or whether a second copy exists anywhere, until you confirm it.

Dig into your company’s process to find out what happens to a file after you save. Where does it go, what copies it, and how far back can you restore it? If the answer is “the cloud handles it,” find out whether the cloud keeps versions or simply mirrors whatever is there now (mistakes included).

Keep working files and synced files apart, and keep at least one copy that nothing syncs to.

Another idea is to practice a restore before you actually need one. Pick a file, attempt to get last Tuesday’s version back, time the process, and work out any kinks that show up on your test. The discussion threads that end badly usually begin with someone learning at the worst possible moment what their backup plan actually was.

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NOTE: We wrote this column based on public discussion in CAD user forums over roughly the past two years. Much of it came from Autodesk Community, with additional threads from a SOLIDWORKS reseller's community forum. We used AI to search those forums, log each account against its source, and draft. We then checked, wrote, rewrote, and edited before publication. Where the forums described how the software behaves, we confirmed it against Autodesk's own documentation. 

How do you handle this problem? Email us and let us know!

This week's Just Tell Jo newsletter is sponsored by:  Vectorworks.