Hey everyone,

I just started using Umbraco and have run into an error when attempting to upload media files in the Media tab. I get an "An error has occurred" message next to the filename of the file that failed to upload.

Console shows:

Failed to load resource: the server responded with a status of 500 (Internal Server Error) http://localhost:53224/umbraco/backoffice/UmbracoApi/Media/PostAddFile

Network tab shows:

)]}', {Message: "An error has occurred.",…} ExceptionMessage : "Object reference not set to an instance of an object." ExceptionType : "System.NullReferenceException" Message : "An error has occurred." StackTrace : " at Umbraco.Web.WebApi.Filters.DisableBrowserCacheAttribute.OnActionExecuted(HttpActionExecutedContext actionExecutedContext) ↵ at System.Web.Http.Filters.ActionFilterAttribute.OnActionExecutedAsync(HttpActionExecutedContext actionExecutedContext, CancellationToken cancellationToken) ↵--- End of stack trace from previous location where exception was thrown --- ↵ at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) ↵ at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) ↵ at System.Web.Http.Filters.ActionFilterAttribute.

The logfile in AppData shows:

2016-03-31 18:39:26,325 [P9052/D3/T47] ERROR Umbraco.Web.WebApi.Filters.FileUploadCleanupFilterAttribute - Could not acquire actionExecutedContext.Response.Content System.NullReferenceException: Object reference not set to an instance of an object. at Umbraco.Web.WebApi.Filters.FileUploadCleanupFilterAttribute.OnActionExecuted(HttpActionExecutedContext actionExecutedContext)

Tried a clean install with a new project and all was well, so I'm at a complete loss what the culprit is in the current project. Any pointers would be much appreciated!