I suspect this is not the same issue but it maybe worth a try:

http://blog.craigbailey.net/2008/03/tip-fixing-ie-so-it-doesn-go-mental.html

>Hi everybody,
>
>I noticed this behavior couple of times already. I have several instances of FireFox as well as IE7 as well as other applications opened. In one of the current instance of IE I want to add a new tab (say, send something to gmail) and then IE7 silently goes down for all sessions...
>
>Quite inconvenient, I would say.
>
>Seems to coincide to my trying to look through MS Help articles (clicking of various links back and forth)...
>
>Oh, well...
>
>---------------------------
>BTW, the thread title should have been read as "Silent "downfall" of IE7" Got bitten with the same bug as Jay, though there were no error messages.