Antivirus Check Fails in APM

Hi All,

 

Can someone help me with below issue.

 

User is connected to VPN from home network, that time user is unable to access one of the share drive & when i checked the logs i can see the below error.

 

"Session_Id=5479b4b4;Session_Variable_Name=session.check_software.last.av.item_1.errors;Session_Variable_Value=Failed to get 'db_signature'. code: -2 (Not implemented) mId: 2 iId: 9"

 

Can someone explain me what & why is this error occurred.