Make a new destination folder for your completed AE render, and navigate to that folder when you set up the comp for rendering in AE's Render Queue.
4 gigs may sound like a lot to you, but AE strains to get anything done with so little memory. It's a cinch you can't use multiprocessing, so turn it off.
Thanks Dave...but no luck. Multiprocessing is turned off and I tried to send the render to a new folder, but same message.
Fixed it/ My file path was lost somehow. Deleted the info in the Render Cue, Selected Comp again, clicked Composition and chose Make Movie...worked great. Got this info from a tutorial by Linora Low.com. Check her out.
Glad you found that helpful, but I never do it that way. When I render a comp, I click on the highlighted "Output To" line in the Render Queue, then navigate to the folder where I want the file to go.
It's never failed me in 15 years of AE rendering.