When you upgrade a computer running App-V 4.5 client to System Center Configuration Manager 2007 SP2, it may break all File Type Associations for virtualized applications. This occur because SP2 installer updates following key in registry as part of Configuration Manager 2007 Service Pack 2 upgrade: HKEY_CLASSES_ROOT\SCCM.VAppLauncher\shell\Open\command. But it doesn’t update other two keys that App-V uses: HKLM\SOFTWARE\Microsoft\SoftGrid\4.5\Client\UserInterface - DDELaunchMSICommand and LaunchMSICommand. This causes all FTAs that were created through a published APP-V app to break, until a time when a new app’s published to machine which triggers client to update key itself. At this point FTAs for newly published app would work but FTAs for all other already existing apps would still be broken.
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