Why is HttpContext.Current null after await?

Please ensure you are writing an ASP.NET 4.5 application, and targeting 4.5. async and await have undefined behavior on ASP.NET unless you are running on 4.5 and are using the new “task-friendly” synchronization context.

In particular, this means you must either:

• Set httpRuntime.targetFramework to 4.5, or
• In your appSettings, set aspnet:UseTaskFriendlySynchronizationContext to true.

More information is available here.