After Effects RAM Preview Not Working: Fix with Empty Disk Cache & Clean Database

When RAM preview stops working in After Effects, it can severely impact your editing workflow. This issue typically stems from memory management errors, cache conflicts, or GPU configuration problems—all of which can be resolved through proper settings adjustments.

• Common Causes
• Comparison Table
• Solution Steps
• Quick Q&A
• Final Checklist
• FAQ

Common Causes

Insufficient memory cache capacity is the most frequent culprit behind preview interruptions. If you don't regularly clear your cache in the preferences, this problem will keep recurring.

Improperly configured GPU acceleration settings can also cause preview freezing. This happens most often when using incompatible or outdated graphics drivers.

Comparison Table

Cause	Symptoms	Solution	Pro Tip
Cache overflow	Excessive memory usage	Clear disk cache	Schedule regular cache maintenance
GPU compatibility	Driver version mismatch	Update to latest driver	Use Studio driver version
Project overload	High-resolution source files	Create proxy files	Work with lower resolution temporarily

Step-by-Step Solution

1. Open Edit > Preferences > Media & Disk Cache (macOS: After Effects > Preferences).
2. Click Empty Disk Cache. If indexing issues persist, also click Clean Database & Cache (media cache/database).
3. Click Choose Folder… (Disk Cache) and select a fast local SSD.
4. Go to Preferences > Memory & Performance and reduce RAM reserved for other applications so After Effects can use more RAM.
5. Open File > Project Settings > Video Rendering & Effects and toggle Mercury GPU Acceleration ↔ Software Only to isolate GPU issues. Update your GPU to the latest vendor driver (for NVIDIA, use the Studio Driver).
6. Save your project file to a local disk (not a network share), then completely quit After Effects and relaunch.

Edit → Purge → All Memory & Disk Cache (Optional: Use when preview memory conflicts occur)

Note: In newer versions (AE 25.2+), High-Performance Preview Playback can stream from the Disk Cache for longer previews, so SSD speed matters. On earlier versions, real-time speed primarily depends on available RAM, effect/layer complexity, and GPU stability.

After Effects Media & Disk Cache preferences screen — showing Choose Folder… (Database/Cache) and Clean Database & Cache options.
UI screenshot from Adobe After Effects.

Additional Solutions

Creating proxy files can significantly improve preview speed. Additionally, temporarily disabling unnecessary layers will effectively reduce cache usage.

If the green preview bar doesn’t fill up during playback, clear the disk cache, adjust RAM allocation in Preferences > Memory & Performance, and restart After Effects.

Special Cases and Alternatives

In managed or corporate environments, working from network shares can add latency and destabilize preview caching. Keep both your project and the Disk Cache on a fast local SSD as a rule of thumb.

Quick Q&A

RAM preview won't start at all?

Try adjusting the memory allocation percentage in preferences, then restart the program.

Should I disable GPU acceleration?

If you suspect compatibility issues, temporarily disable GPU acceleration and test to see if that resolves the problem.

Final Checklist

• 5-Step Summary: Clear cache → Check drivers → Verify project save location
• Quick Fix: Disable GPU acceleration and retry RAM preview
• Essential Check: Always set project location to local disk
• Pre-Work Recommendation: Create project file backup

Frequently Asked Questions

Where can I check error logs when RAM preview freezes?

Enable logging via Help > Enable Logging (or Preferences > General > Enable Logging). For renders, set Render Queue > Log to the desired level. Then inspect the generated log file for clues.

Do I need to clear disk cache every time?

Not necessarily, but if RAM preview errors keep happening, clearing the cache is an effective solution.

References

Adobe Official Help — Troubleshooting guide for After Effects memory and storage settings.