Whenever I add a web-page or file into a Thunderbird email, it crashes my PC. If I copy a URL into an email and then close Firefox before sending the email then my PC does not crash. I have Windows 7 and I have been having this problem for about 3 months. The troubleshooting information mentions a HP 1100 printer which I no longer have and I do not know how to remove that information from Firefox. I removed the driver about 8 weeks ago.