1. Close Internet Explorer, then click the 'Start' button. Type 'regedit' in the search box if you are running Vista or in the run box if you are running older versions of Windows. Hit 'Enter.'
2. Highlight 'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Main\FeatureControl' by clicking on it.

3. Highlight 'New' in the edit menu and click 'Key.'
4. Type 'FEATURE_ERROR_PAGE_BYPASS_ZONE_CHECK_FOR_HTTPS_KB954312' in the new key box and hit 'Enter.'
5. Highlight 'New' in the edit menu and choose 'DWORD Value.'
6. Type 'iexplore.exe' in the value box and hit 'Enter.'
7. Choose 'Modify' in the edit menu and enter '1' in the modification area. Click 'OK.'
8. Close the registry editor and open Internet Explorer to see if the certificate error problem is fixed.