title: Azure Function not logging to Application Insights
body: <p>I have an Azure Functions project that was deployed to a Function App for dev/test and was successfully writing log messages to Application Insights. I published the same project to a new Function App, in the same Azure subscription and now neither App logs anything to Application Insights.</p>
  
  <p>The project was deployed using Visual Studio (15.8.7 with Azure Functions and Web Jobs Tools 15.9.02009.0).</p>
  
  <p>I tried adding a logger entry to host.json to explicitly set the Function category log level to information.</p>
  
  <p>The Azure Functions and Web Jobs Tools extension is up to date in Visual Studio.</p>
  
  <p>I also tried deleting the APPINSIGHTS_INSTRUMENTATIONKEY application setting, and restarting the App, so that then when I clicked on the Monitor tab for one of the functions it went through the wizard to configure Application Insights. At the end of that though, it displayed the message "your app is offline or the application insights sdk needs updating".</p>
  
  <p>Any ideas what could be wrong?</p>