General Error or Out of Memory Continued Frustrations

Hi everyone! I've been searching this forum and have done the solutions provided in some of the workarounds, i.e. deleted preferences etc. I'm still having the same issue: I export a 60 second 1920x1080 QT animation codec sequence from After Effects CS6, import into FCP 7.0.3 and mix audio. I then try to export directly from the timeline, File>Export>Using Quicktime Conversion. Almost immediately I get the "General Error" or "Out of Memory" error. I've tried re-exporting out of AE to no avail. Incredibly frustrating. If I export 1280x720 from AE and try the same thing I get no problems however. What gives? I need this to be full HD. Please help!

MacPro 2x2.4 ghz quad
64GB RAM
NVIDIA Quadro 4000

Thanks!

John

64 GB RAM??? Wow. What are you doing with an old MacPro that you are coming close to even needing 1/4 of that? Time to eBay some of that while it's still gold. :)