Why does Internet Explorer crash?

We have the ability to quote on insurance coverage from a secured web based application. Once the quote is created the producer can create an application to send to perspective customer from within this web based app. When creating the app it uses an adobe accord form which automatically place info on the form and this is were IE crashes.The producer usually has other ie windows open, some are to other secured web sites and local intranet sites and all IE indows crash at same time. I routinely delete cookies and temp int files. Can someone help with why IE crashes. IE version is 6.02 sp1 128 bit encryption. Thanks in advance.