I'm betting the problem is that your windows virtual memory page file is too small (it sounds like you are using Windows.) I had the same problem when trying to render to a separate window. Anything larger than 1300x1300 triggered this error. Increasing my virtual memory minimum setting from 192 to 210 megs fixed the problem and now I can render up to Poser's 4090x4090 maximum. The actual number required may vary from system to system so you may have to experiment a bit. BTW, this is a Windows setting, not a Poser setting. If you are unsure how to change this just ask but also tell me which version of Windows you are using.