It's quite possible that you're running out of RAM. How much do you have? You may be able to fix that if it is a memory issue by adjusting your pagefile size. Right-click My Computer-->Properties-->Advanced-->Click Settings on the performance tab-->Advanced--> Change virtual memory--> set it to at least 4X the amount of RAM in your computer. Restart, and try it again. Oh, and if you have two hard drives, set it on the opposite drive of your operating system(windows). This will also give you a performance boost on normal operations as well.