Two patches released in Microsoft's April batch of security updates are causing system hangs, Windows crashes and the appearance of strange dialog boxes.
The problems stem from a nonsecurity modification to Internet Explorer and a critical fix for a code execution hole in Windows Explorer and affect third-party programs from Google, Siebel and Microsoft's own Windows Media Player.
On April 15, Microsoft released a knowledge base article to acknowledge "problems" in Windows Explorer or the Windows shell after the MS06-015 security update is installed.
That update, Microsoft said, includes a new binary called VERCLSID.EXE that validates shell extensions before they are instantiated by the Windows Shell or Windows Explorer.
On some consumer-facing programs running Hewlett-Packard's Share-to-Web software and Sunbelt's Kerio Personal Firewall, the new binary stops responding.