Outlook Web Access

I am able to log into Outlook Web Access, read my emails, but when I click "reply," to an email, I get  a screen that says, "Internet Explorer has stopped working. a problem caused the program to stop working correctly. Windows will close the program and notify you if a solution is available."  I have not changed anything on my computer but have accepted all Microsoft updaes. I am running Vista. Outlook was working fine until about a week ago and then I started receiving these warnings when I tried to answer emails.  I do not have this problem with my Outlook account only the web version. How do I resolve this issue? Thank-you, Baker House