Hi, I have Win7 64bit with 6GB memory. The Windows System control panel agrees with that showing 6GB ram and nothing about a limitation. But today I was opening a lot of files and the program wouldn't let me open more files after Windows memory use reached 4GB. Task Manager showed 4GB used out of 6GB. I tried opening another file with a different program and my screen flickered and the program shut itself off, so it looks like the problem is with Windows and not the other programs. How do I get Windows to use all available memory not just 4GB out of 6GB? Thanks.