While examining the event logs of one of our Forefront TMG servers, I noticed an error stating that the disk cache failed to initialize.
Event ID: 14176
Source: Microsoft Web Proxy
Disk cache Drive:urlcacheDir1.cdat failed to initialize. Some errors were encountered when ISA Server restored specific data cache files. ISA Server will now attempt to recover these files. These errors may have occurred because there was not enough time to complete all necessary shutdown operations, when ISA Server was previously shut down. To avoid this in the future, you can increase the value of the HKEY_LOCAL_MACHINESystemCurrentControlSetControlWaitToKillServiceTimeout 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 of the failure (internal code: 503.63184.108.40.2060.166).
No functionality was lost, but the error caught my attention and I found a Microsoft KB that described this error:
In my case, McAfee Antivirus was active and as described by the KB, you should exclude the disk cache directory within your virus scanner. I already had an exclusion for the on-access scanner but no exclusion was yet active for the on-demand scan. The time that this error occurred, was about 30 minutes after the on-demand scan was executed.
I just added the exclusion for the on-demand scan and hopefully this will prevent the error from appearing.