Web Site Stops Responding for 15-25 seconds

There are a number of reasons that a web site could have a delay (hang) that could cause problems.  I am going to talk about a common one that we see which is the CRL.
What we have seen in the past is the Crypto API?s are trying to update the Certificate Revocation List (CRL) from the internet. If the server doesn?t have permission to access the internet you get the delay while we wait for the request to time out.
The server is trying to get the certificate revocation list from one of these:
http://crl.microsoft.com/pki/crl/products/CodeSignPCA.crl
http://crl.microsoft.com/pki/crl/products/CodeSignPCA2.crl
There are a few ways to resolve this.  The callstack will look like:
0x0611b6b4 0x77e41817 kernel32!WaitForSingleObjectEx+0xac
0x0611b70c 0x77da1bbb advapi32!Bas ...