Quick answer
Close Word, delete everything in %temp% and C:\Windows\Temp, then restart Word. If it still fails, go to File > Options > Add-ins and disable all COM add-ins. That clears 90% of these cases.
Why this error is a lie
Word says 'There is not enough memory or disk space' but your drive has 200GB free and you've got 16GB of RAM. What's actually happening here is Word's own temporary files have spiraled out of control. Every autosave, every tracked change, every embedded object gets written to %temp%. When that folder fills up with hundreds of thousands of small files, the file system gets sluggish, and Word's save routine times out. It reports that as a memory or disk problem because those are the only failure codes it has.
Another culprit: a broken add-in. Add-ins load into Word's process and can hold file handles open. If an add-in locks the temporary file Word needs to write, the save fails with the same deceptive message. You'll see this more often after an Office update or a third-party PDF converter installation.
The fix, step by step
- Close Word completely. Make sure it's not running in the background. Check Task Manager (Ctrl+Shift+Esc) and end any WINWORD.EXE processes.
- Clear your temp folders. Press
Win+R, type%temp%, hit Enter. Select all files (Ctrl+A) and delete them. Some will be in use — skip those. Then do the same forC:\Windows\Temp(you might need admin rights). This frees up space and, more importantly, removes the thousands of stale Word temp files that start with~$. - Restart Word and try saving. If it works, you're done. The reason step 2 works is that Word regenerates its temp files cleanly on the next save, and the file system no longer has to fight through a mountain of old ones.
- If the error persists, disable all COM add-ins. Go to File > Options > Add-ins. At the bottom, set the Manage dropdown to COM Add-ins and click Go. Uncheck everything, click OK, restart Word.
- Still stuck? Repair Office. Go to Control Panel > Programs > Programs and Features, find Microsoft Office, right-click and choose Change, then select Quick Repair. If that fails, do the Online Repair — it takes longer but replaces corrupted files.
Alternative fixes if the main steps don't work
Check your antivirus
Real-time scanning can lock Word's temp files mid-write. If you're on Windows Defender, add an exclusion for your Documents folder and %temp%. The reason this helps: the AV scans every file Word creates, and if it's slow, Word's save operation times out. You'll see this pattern on older machines with Defender and a mechanical hard drive.
Reset Word's registry keys
For advanced users: export and delete the HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Word key, then restart Word. This resets all Word settings to default. Back up the key first — you'll lose custom dictionaries and toolbar customizations. This is a nuclear option, but it fixes cases where a corrupted option is causing the save failure.
Change the autosave location
If your default save location is a network drive or OneDrive, Word might be choking on latency. Save locally to C:\Users\YourName\Documents and see if the error goes away. This isn't a permanent fix, but it tells you the problem is network-related, not local.
Prevention tip
Set Windows to clean temp files automatically. Open Settings > System > Storage, turn on Storage Sense, and set it to clean temp files every week. Also, uninstall add-ins you don't use — they're the second leading cause of this error. And if you're on OneDrive, make sure you're not running out of cloud storage; Word can misreport a full OneDrive quota as a local disk error.
One more thing: if you've got a massive document (500+ pages with embedded images), the error might be legit. Word's 32-bit version tops out around 2GB of memory. If that's your situation, switch to the 64-bit version of Office. It won't fix temp files, but it gives Word room to breathe.