IE8 Freezes/Not Responding Unless Intrusion Prevention Add-On Disabled

IE8 suddenly quit functioning for me this afternoon around (approximately) 5pm EST.  Completely froze up and quit responding although I had done nothing but try to switch tabs.  I killed the process with Task Manager (I run Vista 32 bit OS btw) and discovered the same problem when trying to restart IE8 -- it froze immediately and was totally unresponsive.  Same result after rebooting.  Finally got it to work by disabling the Symantec Intrusion Prevention Add-On which is the culprit to this sudden problem.  Once I did that (disabled your add-on), everything works great.  I have NEVER had to do this (disabling your add-on) before and am wondering if you guys recently updated something that may have broken this in some way?  I don't like the idea of running IE8 without Intrustion Prevention enabed but it seems I have little choice for the time being.  Before you suggest it, let me be clear: I haven't installed or changed anything on my system recently and it is DEFINITELY freezing up IE8 if your Intrustion Prevention Add-On is enabled and works fine if just that one add-on (yours) is disabled.  Been running with no problems with your software for a long time ... until right now.  What gives?

 

J Pittman