Troubleshooting "Other Error (Internal error, 42)"
If you are using Kaspersky or Panda:
This issue occurs because the Kaspersky and Panda virus scanning engines unpack compressed archives in memory. A 400E ProxyAV appliance may run out of memory on complex archives and fail to scan. In ProxyAV 220.127.116.11 or later, the engine will report the correct error message of "Insufficient temporary storage space". You may choose to block or serve content due to this error by going to the "Antivirus - Scanning Behavior" page and selecting either "serve" or "block" on "out of temporary storage space" exception.
If using "serve" you may further refine this in SG policy by using 'ICAPerror code'.
If you are using Sophos:
This issue occurs because the Sophos virus scanning engine has recently increased its per-process memory requirements. A 400E ProxyAV appliance is more susceptible to this problem because of limited RAM resources. To address this issue the number of small object scanning threads has been reduced in ProxyAV 18.104.22.168. If you are unable to update to ProxyAV 22.214.171.124 at this time please contact Support so a manual procedure can be provided.