Disable CRL Checking in IIS 6

from here:

The simplest way to disable the CRL check is by using adsutil.vbs, located in the \inetpub\adminscripts folder. The following command will disable the CRL check for the first web site:

cscript adsutil.vbs SET w3svc/1/CertCheckMode 1
To re-enable CRL checking, do:

cscript adsutil.vbs SET w3svc/1/CertCheckMode 0