Microsoft has released a Hotfix for Microsoft Application Request Routing for IIS7

This hotfix addresses an intermittent performance degradation in Application Request Routing v2.0/v2.1 when disk caching is used. More detailed information about this hotfix is in the Microsoft Knowledge Base article KB2406763. Application Request Routing QFEs are accumulative. This KB (KB2406763) also includes the fixes for KB2281517 and KB2301898.

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