Bowing to pressure from European antitrust regulators and rival security vendors (especially Symantec and McAfee), Microsoft has agreed to modify Windows Vista to better accommodate third-party security software makers. In a press conference Friday, Microsoft said it would configure Vista to let third-party anti-virus and other security software makers bypass 'PatchGuard,' a feature in 64-bit versions of Windows Vista designed to bar access to the Windows kernel. Microsoft said it would create an API to let third-party vendors access the kernel and to disable the Windows Security Center so that users would not be prompted by multiple alerts about operating system security. In addition, Redmond said it would modify the welcome screen presented to Vista users to include links to other security software other than Microsoft's own OneCare suite.

Some security vendors expressed some concerns to the Commission, and to us, that they had previously used access to the kernel to facilitate features in their own product and that they would no longer be able to do so. We were concerned that it would be a mistake for the future of computers if PatchGuard were to be removed or eliminated. We devised a new engineering approach that will create and extend new kernel level APIs so that PatchGuard will be retained, the security of the kernel will be protected, and yet security vendors will have an opportunity to meet their needs through these kernel level API extensions. We felt that this was again the right kind of solution that meets the needs and obligations that we have under competition law, whilst also meeting the needs of computer users around the world.