Microsoft Windows Root Certificate Security Issues

In the default configuration for Windows XP with Service Pack 2 (SP2), if a user removes one of the trusted root certificates, and the certifier who issued that root certificate is trusted by Microsoft, Windows will silently add the root certificate back into the user's store and use the original trust settings. This prevents a Windows XP SP2 user from declaring a Microsoft-trusted certification authority as untrusted unless the user turns off the Windows component that controls this feature.

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