I have problem with cache stop web proxy service and say this occurred because there was not enough time to complete all necessary shutdown operations, when ISA Server was previously shut down. To avoid this in future, you can increase the value of the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\WaitToKillServiceTimeout registry key. Identify the reason for cache failure by examining previous recorded events, or the error code. The error code in the Data area of the event properties indicates the cause