I'm going to run a test on the same project in AE CC 22.214.171.124 and see what happens...
OK. So, here's what happened in AE CC 126.96.36.199 using my 5000 x 5000 Quicktime source files in the project. Failed. Error 7 :: 66 again.
Happened at approximately the same time 16:06 of 30:00.
I watched at RAM data at the bottom as it rendered. The % kept climbing as it rendered. When it got to 80-82% of 64GB it leveled off, then it would go from 82% to 81% to 80% then back up to 81%. Looked like AE was regulating the amount of RAM used. But it steadily kept rendering with very little slowing. Then around 12 seconds (comp time) it went past 82% and climbed all the way to 100% of 64GB RAM and failed. Seems to do the same in AE CC 2014 13.0.2.
3000 x 3000 source Quicktimes work ok and don't go past the regulated % of RAM. Seems strange and a shame though. Obviously AE can handle the large resolution source video files. If I was rendering a 10 second file movie I'd be golden and the error would most likely never happen. We are doing lots of 4K for up coming TV projects so the higher resolutions will be very important.
Any other tests I can run to help sort this out?
Try opening up the secret preferences by holding down the shift key when you click preferences>general. The secret page is at the very bottom. Set your system to purge every 5 or 10 frames and give that a try.
Tried the secret menu, purging every 10 frames, no luck
Please somebody help me with this I am using Adobe after effects CC 2015 running on a macbook pro 2010 with 2.47 ghz and 4 gb ram Please help me with this!