If you want to know how to get your “view source” to work again in IE read on.
Most of the people I know suddenly experience that it suddenly is impossible to use the “View source” functionality in the Internet Explorer. The problem occurs due to a bug in IE if you’ve set your Temporary Internet Files too high. If you decrease this setting to less than 80MB the problem stops. If not, try to delete all temporary files.
IMPORTANT Update: This sounds strange, but if you have a shortcut to Notepad on your desktop it will also prevent you from viewing source!!!