System - Windows XP Professional, 1.8Ghz Processor, 512Ram, 80Gb Hardrive, Sapphire Radeon 9600Pro 128Mb Graphics Card. Have re-installed Windows, due to various problems. Now I am experiencing memory problems when I attempt to install large programmes like Microsoft Flight Simulator 2004 and Microsoft Train Simulator, etc. After a few minutes the screen displays the following message . . . Installation stopped - caused by low memory (Low disk space for swapping file). Has anyone any ideas what has happened and how I can cure it.