Application Launch triggers requests for crl.microsoft.com and ctldl.windowsupdate.com

c#, certificate, windows, winforms

Solution

I'm not 100% sure but I guess you have to disable this behavior by setting a grouppolicy:

I used `gpedit.msc` to verify that below steps are possible. If they resolve your issue exactly I can't verify.

- In the Local Group Policy Editor, under the Computer Configuration node, double-click Policies.

- Double-click Windows Settings, double-click Security Settings, and then double-click Public Key Policies.

- In the pane on the right side, double-click Certificate Path Validation Settings.

- Click the Network Retrieval tab, click to select Define these policy settings, and then click to clear the Automatically update certificates in the Microsoft Root Certificate Program (recommended) check box.

- Click Ok, and then close the Local Group Policy Editor.

There is also a tab TrustedPublishers, if you 'define the policy' you can leave the two checkboxes at the bottom for verifying certificates unchecked.

I'm also unsure about the SqlServer Compact stuff but that might be solved by adding a config setting to the config of the application because AFAIK the SqlCE engine is loaded in process of your app.

<configuration>
    <runtime>
        <generatePublisherEvidence enabled="false"/>
    </runtime>
</configuration>

based on a blog post of Mark Russinovich

Problem

I am working on a signed application. The application is going to be deployed to a closed network where most outbound calls will not be allowed. I noticed when I start the application, which is signed and uses SQL Server CE 4, that about 6 web calls are made. I get one call to `crl.microsoft.com`, two calls to `ctldl.windowsupdate.com`, and then 3 calls for the certificate authority. The problem is that since this is a closed network, all of these calls are returning 502 errors. I believe that these calls may be adding noticeable lag time to the launching of our application. What are these windowsupdate.com requests and how do I stop them from being called?

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