When exception is thrown in production with WebMarkupMin turned on... error page returns as garbled/garbage/weird characters.

To give as much information as possible: Controller: Research, ActionResult: Finish makes a call to a [NonAction] void FulfillPapers in the BaseController and while processing papers e-mailer throws an exception, this is expected (which is intercepted by Application_Error at the application level. Which I then run ErrorController.ExecuteErrorController(httpContext, httpContext.Request, exception); and throw the generic error page for the customer. This page returns back garbled when it is running in production, staging/test works fine. Perhaps the compression filter is being applied twice once on the original page and once again on the new page??? Any thoughts what to look for?

[Taritsyn]

Be sure to try the code from my previous comment. It seems, that your code from the Application_Error method does not allow my error handler to run.

[Taritsyn]

Try adding the following code to beginning of the Application_Error method:

HttpContext httpContext = ((HttpApplication)sender).Context;
if (httpContext.Items.Contains("originalResponseFilter"))
{
	var originalResponseFilter = httpContext.Items["originalResponseFilter"] as Stream;
	if (originalResponseFilter != null)
	{
		httpContext.Response.Filter = originalResponseFilter;
	}
}