Verisign Certificate and IIS4 on NT4

I installed a Verisign Certificate on NT4 server running IIS4.0 When I go to this site from the browser I get a “Issuer is untrusted or unknown error” I can only click yes or no to continue and I also have a view certificate button. when I view it is all correct. after I click yes on this I get a blank dialog box. asking me to pick a cert but nothing shows up. After clicking ok on the blank dialog it goes to the secure site no problem and I get the lock in the browser. I get different messages with different IE browsers on different OS platforms. any help I would appreciate.

Thanks
Brian