Which version of IE are you using?
In any case try both of these:
a)Open Internet Explorer
b)Select the Tools option and click on Internet Options.
c)Select the last tab Advanced and set all the settings to default including the security settings by selecting the option button Reset.
d)Click on Ok and restart the Internet Explorer.
And
a)Open Internet Explorer
b)Select the Tools option and click on Internet Options.
c)In the Security Tab select the Trusted sites Zone and click on Custom level
d)Scroll down and enable the option Display mixed contents
e)Also enable the option don't prompt for client certificate selection when no certificates.
f)Click on OK and restart the Internet Explorer.
Cheers
Steve