Some more info: When the render failed this came up: After Effects warning: logged one error - "error: Rendering error while writing to file "C:\Users\Omar\Documents\(files name)". Unknown error! (-1610153453)"
That's a Quicktime error code. If it always happens at the same point, most likely the source footage is damaged. Other than that simply try saving to a different location.
I rendered it out as a tiff image sequence and saw that there was white frames in between the clip. So, I converted the file in sony vegas to .wmv and .mp4 and replace the original footage with it but the render still failed both times. Also, saving it to another location did nothing. Im not sure what is is because when i checked the logs it didn't say anything. Do you think a reinstallition of quicktime will solve the problem?
This issue was plaguing me for a solid hour, but with some extended googling I found out I'd accidentally made my work zone one frame long (I was playing around with keyboard shortcuts...) I set my work zone back to the right range in the comp I needed to render and now it's all good.
It would've been nice if the error message mentioned that in future, might have been a little more helpful than UNKNOWN ERROR! (-RANDOM NUMBERS!)
Hope this helps!