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CRL does not automatically renew under Windows

One of my sites is behind a proxy server. At that site, some computers (a couple of XP machines, a Vista laptop, and now our new Server 2008) do not update their Verisign CRLs. These machines are not on a domain. I have been unable to find any information on how this mechanism works, or how to trigger it manually. Other machines at the site seem to be fine.

This is a major issue for us, because we use Patchlink over https. When that CRL becomes invalid, Patchlink stops working until I manually import the certificate by downloading it from Verisign and installing it by hand. Anyone have any ideas?

Thanks!
Ken
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Paranormastic
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This should be an automatic process.  The CRL has a 'next update' tag within it, instructing the client when they should start looking for the next CRL.  If this is not being downloaded automatically, I would suspect that your firewall is blocking the traffic.  Typically the CRL will be pushed over http (TCP port 80).
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yunbukogar

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Hi Paranormastic, I was thinking the same thing. What I can't figure out is why some work, but some don't. I also don't know what server the serves the CRL. Anyone have any idea or some idea how to find out? Is it as simple as http://crl.verisign.com? 
Assuming its the same as the one for the cert they use on their own site, it would be:
http://EVIntl-crl.verisign.com/EVIntl2006.crl

You can look at your certificate's properties and on the Details tab look for CRL Distribution Point (CDP) attribute and select that.  In the box in the bottom half it will show where the CDP location(s) are.

You can also try: internet options - content tab - Clear SSL State

Can also try clearing temp internet files, history, etc. and if there is a proxy to clear that out - maybe some servers are set to use a proxy and some aren't and the proxy is serving a stale copy of the CRL.
Even if your hardware firewall is set up correctly, don't forget about any software firewalls that you might have installed, too ;)
Hi Ken,
Can the infected computers reach the internet? Is this problem located to only computers not joined to the domain? If so it could your proxy settings are not configured correctly on the affected machines.

Also, opening the local computer certificate store through the mmc -> certificates, in the details fan, you shold be able to see the CRL distribution points. Try copy/paste the URL's into Iexplorer and see if you get a download CRL prompt...or perhaps an error indicating the issue.

Cheers,
Greenhelmet
 
Hi guys,

If I download the CRL manually, it works fine. I do have to install it by hand into the physical store, but it works until it expires again. AFAIK, the proxy is correct (or at least the same on computers that have the problem and computers that don't.)
Hi Greenhelmet,

I'm looking at the mmc/certificates now, and I have the CRL. I don't see any CRL distribution points listed, but if I go to the website of my server, I can get the CDP there.

Looking at the cert in the mmc, it says the next update is Wednesday, April 29, 2009, 12:15:29 PM, exactly 2 weeks since I last installed it.

I'm thinking perhaps it tries to update certs using the localsystem account, which does not have a proxy set up for it. Is there any way to set that up--or set it up for the account it does use?
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