Yeah, that error is annoying as hell. You're mid-render and suddenly After Effects nukes its own cache. But I've seen this a hundred times, and the fix is almost always the same.
The Quick Fix
Open After Effects and go to Edit > Preferences > Media & Disk Cache (on a Mac it's After Effects > Preferences > Media & Disk Cache).
Look at the Disk Cache section. You'll see a folder path and a size limit. Here's what to do:
- Click Choose Folder and pick a fresh folder. Do not use a network drive or an external USB drive. Use a local internal drive with plenty of free space. I recommend something like
C:\AE_Cacheon Windows or/Users/yourname/Library/Caches/After Effectson Mac. - Set the Maximum Disk Cache Size to a reasonable number. If you have a 512GB SSD, go with 50 GB. If you're on a 256GB drive, drop it to 20 GB. Don't set it to 0 — that disables the cache and you'll get worse performance.
- Click OK and restart After Effects.
That's it. 90% of the time this kills the error. The cache will rebuild itself from scratch, but it beats seeing that error every five minutes.
Why This Works
The root cause is almost always one of two things:
- The cache folder path is invalid. Maybe you moved the folder, deleted it, or it's on a drive that wasn't mounted when AE started. When After Effects can't write to that path, it doesn't just fail silently — it purges the whole cache and throws that error.
- The size limit is set to something dumb. If you set it to like 2GB on a project with heavy 4K comps, AE will constantly purge to stay under that cap. It's like trying to stuff a sleeping bag into a sandwich bag.
By pointing AE to a clean, local folder and giving it a sane size limit, you eliminate both failure points at once.
Less Common Variations
Sometimes the fix isn't that simple. Here are other scenarios I've run into:
1. The folder is on a drive that goes to sleep
If your cache is on a secondary HDD that spins down after a few minutes, AE can't wake it fast enough. The solution is to move the cache to your OS drive (C: on Windows) or an always-on SSD. Same fix as above, but worth calling out because people blame AE when it's really the drive.
2. Permissions are screwed up
On a corporate machine, sometimes the cache folder loses its write permissions. Check by right-clicking the folder, going to Properties > Security (Windows) or Get Info > Sharing & Permissions (Mac), and make sure your user has read/write access. If not, fix the permissions or pick a new folder.
3. One specific project triggers it
If the error only happens with one project, check if that project has a custom output module or a script that writes to a weird location. Also check for any expressions that reference file paths — those can mess with the cache. But honestly, that's rare. Usually it's the global settings.
4. Corrupted cache files
Sometimes the cache database itself gets corrupted. The fix is to just clear the whole cache manually. Go to the same preferences window, click Clean Database & Cache, and let AE rebuild. Then restart.
Prevention
Once you've fixed it, don't let it come back. Here's my routine:
- Set a monthly calendar reminder to clear your cache. Use Edit > Purge > All Memory & Disk Cache or just delete the cache folder contents when AE is closed. Keeps things tidy.
- Don't set the cache size to more than 50% of your free drive space. You need room for your OS, your project files, and temp files from other apps.
- Never put your cache on a thumb drive or a network share. It will fail, every time.
- If you use multiple versions of After Effects, give each one its own cache folder. They don't share well.
That's the whole story. Fix the path, fix the size, and move on. You've got renders to finish.