Microsoft released yesterday, May 22, 2007, a non-security update designed to resolve functionality issues with the Windows Installer. The company's latest operating system, Windows Vista, is not impacted by the new high-priority update, as it was released for aberrant behavior in Windows XP, Windows Server 2003 and Windows 2000.

Users of all supported versions of the Windows platform with the exception of Windows Vista, have experienced severe loss of system responsiveness following Windows Update or Microsoft Update scans for updates using Windows installer. The new update from Microsoft addresses Windows Installer (MSI installer).

"This update applies to currently supported versions of Windows except Windows Vista. The update addresses an issue you may experience where systems may become unresponsive when Windows Update or Microsoft update is scanning them. This update is being released through Windows Update, Microsoft Update and Automatic Updates. I want to note that this update will install correctly even if you're experiencing this issue. However, the issue may prevent you from installing other updates (including security updates) until you apply this new update, so we encourage customers to apply this right away," Christopher Budd, Security Program Manager with the Microsoft Security Response Center.

System unresponsiveness associated with Windows Update or Microsoft Update scanning for Windows Installer updates is not the only symptom encountered by users. Additionally, svchost.exe will produce an access violation error. Consequently, the Server service and the Workstation service will both stop as a result of the access violation. Moreover, scans performed by Windows Update or Microsoft Update can also generate memory leaks on the affected version of Windows. And last but certainly not least, the WU and MU scans can be prolonged for hours.

According to Microsoft, the new update for Windows Installer will be served via Automatic Updates, and even the systems targeted will experience no issues deploying the fix.