After Effects 'Out of memory' error with 64 GB RAM — real fix

The 30-second fix: Empty disk cache

Before you do anything else, this solves it half the time. After Effects caches rendered frames to disk. When that cache fills up — and it will with 64 GB RAM — AE just stops and throws the error. It's dumb, but that's how it works.

1. Open After Effects. Go to Edit > Purge > All Memory & Disk Cache. Or hit Ctrl+Alt+Shift+/ (Windows) or Cmd+Option+Shift+/ (Mac).
2. Wait for the progress bar to disappear. Then try rendering again.

Had a client two weeks ago who restarted his machine three times, reinstalled AE, still got the error. This took 15 seconds. He was not happy, but it worked.

The 5-minute fix: Tweak memory and cache settings

If purging didn't stick, the problem is AE's default settings. Adobe assumes you're running 8 GB. With 64 GB, you need to crank up reserved RAM and kill the disk cache limit.

1. Go to Edit > Preferences > Memory & Performance (Windows) or After Effects > Preferences > Memory & Performance (Mac).
2. Set RAM reserved for other applications to 2 GB. Don't touch 4 GB. This tells AE to use the other 62 GB for itself.
3. Now go to Preferences > Media & Disk Cache.
4. Set Maximum Disk Cache Size to 100 GB. Yes, 100. If you don't have that much free space, set it to whatever you can spare — 50 GB minimum. AE will fill it fast.
5. Click Clean Database & Cache. This wipes old, stale cache entries that clog things up.
6. Restart After Effects.

I've seen people set reserved RAM to 8 GB thinking it helps. It doesn't. You're just starving AE. Keep it at 2 GB unless you're running other RAM-hungry apps simultaneously.

The 15+ minute fix: Disable multiprocessing and clear all caches manually

If you're still getting the error after the first two steps, something deeper is corrupting the render pipeline. This happens most often with projects that use heavy expression-driven assets or third-party plugins like Trapcode Particular or Element 3D.

1. Disable multiprocessing. Go to Preferences > Memory & Performance. Uncheck Enable multiprocessing. This forces AE to render on a single thread. It's slower but more stable. For heavy comps, this alone can stop the error cold.
2. Manually delete disk cache folders. Close After Effects. Navigate to:

Windows: C:\Users\[YourUsername]\AppData\Roaming\Adobe\After Effects\[version]\Disk Cache\
Mac: ~/Library/Preferences/Adobe/After Effects/[version]/Disk Cache/

Delete everything inside. Don't just use AE's purge — some corrupt files survive that. Manual deletion nukes them completely.

3. Reset AE preferences. Hold Ctrl+Alt+Shift (Windows) or Cmd+Option+Shift (Mac) while starting After Effects. Click Yes when asked to delete preferences. This nukes all custom settings, but it also nukes any corrupt preference file causing the error.
4. Check your media drives. If your cache drive is an external USB 3.0 drive or slow SSD, AE chokes. Move the cache to your fastest internal NVMe or SATA SSD. Go to Preferences > Media & Disk Cache and change the cache location.

What's actually happening? The tech behind error 12 :: 0

Error 12 :: 0 means After Effects tried to allocate memory — either RAM or disk cache — and the system said no. With 64 GB, it's almost never RAM exhaustion. It's almost always:

• Disk cache full: AE fills its cache aggressively, then can't write new frames.
• Corrupt cache: A single bad frame in the cache poisons the whole render.
• Multiprocessing conflict: On systems with many cores (12+), AE's multiprocessing can cause memory allocation conflicts.

I once spent four hours troubleshooting a client's system — 128 GB RAM, Threadripper. Error 12 :: 0 every 30 seconds. Turned out his disk cache was on a network drive. Moved it to local SSD. Problem gone.

When to just give up and restart

Sometimes — rare, but happens — the error is caused by a memory leak in an expression or a corrupt frame in your comp. If you've done all the fixes above and the error persists, try this: Save your project, close AE, restart your computer, reopen the project. Do not purge or tweak anything. Just try rendering immediately. If it works, the issue was something in your session that cleared on reboot. If it doesn't, it's the comp itself — try rendering in halves, or pre-render heavy elements.

One more thing: if you're using After Effects 2023 or earlier, consider updating to 2024. Adobe fixed a known memory allocation bug in version 24.2 that caused this exact error on high-RAM systems. I've seen it twice — both times, updating was the only fix.