NullReferenceException :Object reference not set to an instance of an object.

Hi Team,

I am seeing  a lot of Null reference exception in the Windows Event viewer related to HTTP.

Following is the Error Details:

Event code: 3005 
Event message: An unhandled exception has occurred. 
Event time: 2/3/2017 3:30:35 PM 
Event time (UTC): 2/3/2017 2:30:35 PM 
Event ID: qwerty6108bec9b62e4ef1cc5 
Event sequence: 1646 
Event occurrence: 7 
Event detail code: 0 

Application information: 
Application domain: /LM/W3SVC/2/ROOT/appname-1-131443322445665693402789 
Trust level: Full 
Application Virtual Path: /pathname 
Application Path: D:\path\folder\sso\ 
Machine name: SERVER150

Process information: 
Process ID: 10788 
Process name: w3wp.exe 
Account name: Domain\username 

Exception information: 
Exception type: NullReferenceException 
Exception message: Object reference not set to an instance of an object.
at AppHandlers.FileHandler.ExtractResource(HttpContext context, String[] incoming, String& extension, String& resourceName)
at AppHandlers.FileHandler.WriteResource(HttpContext context, String[] incoming)
at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

Request information: 
Request URL: https://mywebsiteurl.com/
Request path: /urlpath
User host address: IP address of client 
User: 
Is authenticated: False 
Authentication Type: 
Thread account name: Domain\username

Any help is appreciated