maybe u can try my suggestion:
Can you run IE8 in Safe Mode with network?
Please try to run IE8 from C:\Program Files\Internet Explorer in Normal Mode. If it doesn’t work, I suggest you run a tool named Process Monitor to monitor system behavior.
If possible, please save the log and upload to Windows Live SkyDrive (http://www.skydrive.live.com/)
and share the URL with us.
Thank you for your cooperation. I am looking forward to your reply.
for more info please visit http://www.techyv.com/questions/internet-explorer-8-wont-start