Microsoft Support Team's IIS Blog

Configuring FTP 7.5 with Host Header and SSL

2009-11-06T00:04:00Z

FTP 7.5 comes with new features like supporting Host headers (Virtual host) and SSL. For compatibility purposes, FTP clients can check whether the FTP server supports host headers by sending a FEAT command to check for supported features. An FTP server would respond with HOST being one of the extended features supported by it and from here on client can use this feature. There are two ways of using this feature currently by the FTP clients: 1. They can send the virtual host name along with the Username...(read more)

Configuring DebugDiag to Automatically Capture a Full User Dump on a Managed Function

2009-10-01T18:30:00Z

I recently worked an issue with a customer where we needed to capture a full user dump of the IIS worker process when a specific function was being called. The problem was that the function was in managed code. I thought it would be good to share how to do this with the Web Topics Community. I will first show how to set a managed breakpoint in a normal debugger. Then I will show how to automate it with DebugDiag, and have it take an action of creating a full user mode dump file when the breakpoint...(read more)

A Tale of Two Developers and Visual Studio Sites and Apps

2009-09-30T13:40:00Z

We've encountered several scenarios in which customers have multiple developers working on a single web application in Visual Studio. In such cases, it's not uncommon for each developer to be working on a portion of the application. There isn't any problem in working with this way, but you may encounter some very real problems when you deploy your application unless you plan in advance. The Scenario Suppose you have two developers working on your web application. Developer A (we'll call him John...(read more)

ASP.NET MVC: What is it and should I use it?

2009-09-01T19:49:00Z

In March of this year, we released ASP.NET MVC. Since then, many ASP.NET developers have been perplexed about MVC. Many developers aren't quite sure what MVC is and what it means for ASP.NET developers. Many more developers have some level of understanding when it comes to MVC but are not sure when it should be used and why. This post will hopefully shed some light on some of the confusion surrounding MVC. More Info You can download ASP.NET MVC from the ASP.NET MVC site . A more convenient means...(read more)

High memory in IIS due to scriptproxy.dll

2009-08-18T21:15:00Z

One of my customers had a problem on his IIS server, where the IIS process hosting his web application was suffering from very high memory utilization over time. Eventually the process got so high in memory that the web application became completely unresponsive and incoming requests were no longer getting served. Based on these details, we began troubleshooting the issue as a memory leak/high memory issue. The first step was to capture a memory dump of the problematic process, when its memory usage...(read more)

Deadlock when storing Asp.net sessions in SQL server during peak load

2009-08-12T21:35:06Z

When there is more than 1 server in web farm scenario it is an obvious choice to go for session out-of-proc either with SQL server or State server. While storing session with SQLServer if you see issues with SQL deadlock during peak loads involving DeleteExpiredSessions . It goes like this… Looking at the current implementation of the DeleteExpiredSessions stored procedure: CREATE PROCEDURE DeleteExpiredSessions AS DECLARE @now DATETIME SET @now = GETUTCDATE() ...(read more)

Using ProcDump.exe to monitor w3wp.exe for CPU spikes

2009-08-07T23:12:26Z

Procdump is a light weight Sysinternal's command-line utility whose primary purpose is monitoring an application for CPU spikes and generating crash dumps during such spikes which an administrator or developer can use to determine the cause or to share the dump with PSS for further analysis. It also can serve as a general process dump utility that you can embed in other scripts. It completely eliminates the need to maintain different utilities like Debug Daig 1.1 for 32 bit processes and adplus for...(read more)

IIS7 (and above) – Using FREB to capture dumps for a long running request

2009-08-04T17:38:13Z

In my previous post , I wrote about using FREB to troubleshoot a simple error message to identify the module which sets the error. For this post, let’s assume we are troubleshooting a slow running page (any page, be it aspx, asmx, html, etc). Not always I would recommend you to collect a dump to understand what’s going on inside. There are a few other ways to troubleshoot a slow running page, say enabling FREB to find out which module is taking long time to process, using RSCA (runtime status control...(read more)

Uploading a file using FileUpload control fails in IE8

2009-07-27T18:36:06Z

I had another interesting customer issue this week, where in uploading a file using the FileUpload control was failing only with IE8 . As you would do with any client-side issue, I started by collecting Fiddler traces for both the working (IE7) and non-working (IE8) scenarios. Following were the observations: · IE 7 Content-Disposition: form-data; name="targetFile"; filename="C:\Users\<username>\Desktop\test.txt " · IE 8 ...(read more)

In-Proc Session State Management

2009-07-22T02:51:08Z

What is ASP.NET Session? A session is defined as the period of time a unique user interacts with a particular web application. HTTP is a stateless protocol, in the sense that a Web server is concerned only with the current HTTP request for any given Web page. The server retains no knowledge of previous requests. The stateless nature of HTTP requests presents unique challenges when writing Web applications. ASP and ASP.NET applications maintain a user’s session using a feature called session state...(read more)

Getting the Sys.WebForms.PageRequestManagerParserErrorException while making an AJAX callback

2009-07-21T19:51:38Z

Recently I encountered an issue wherein our customer was running into a client side AJAX exception, Sys.WebForms.PageRequestManagerParserErrorException , while trying to make an Async Postback from an ASPX page. This exception was happening for all the clients in a specific network and looked like this: --------------------------- Microsoft Internet Explorer --------------------------- Sys.WebForms.PageRequestManagerParserErrorException: The message received from the server could not be parsed. Common...(read more)

“Parser Error Message: This implementation is not part of the Windows Platform FIPS validated cryptographic algorithms.” when .net page has debug=”true”

2009-07-20T16:37:00Z

Recently, I came across an issue where the customer faced an FIPS (Federal Information Processing Standards) related error on the .aspx pages which had debug=”true”. His ASP.net application was hosted on IIS7 running on Windows Server 2008 SP2. And, he was able to reproduce the issue using a very simple page. The error message was: Looking at the error, we know that there are articles like KB 911722 and a good blog - Enforcing FIPS Certified Cryptography which discuss the same issue. In Windows Server...(read more)

Troubleshooting HTTP 401.3 errors with Process Monitor

2009-06-26T01:16:00Z

Last week I posted the following blog which showed how to use Process Monitor to troubleshoot service startup issues. http://blogs.msdn.com/webtopics/archive/2009/06/16/troubleshooting-service-startup-issues-with-process-monitor.aspx To continue on that topic, I ran across another issue recently where Process Monitor was again very helpful in troubleshooting. Problem – When browsing ASP pages, we were getting below error in the browser. Browsing any HTML page worked fine. HTTP Error 401.3 - Unauthorized...(read more)

How to Add a Locked Header Row to an ASP.NET GridView Control

2009-06-24T00:22:00Z

The GridView control is often used to display tabular data, much like an Excel spreadsheet. However, unlike Excel, the GridView control doesn't have any automatic way of locking the header row so that it doesn't scroll out of view. Check out this example of a GridView within a DIV with the overflow-Y property set to scroll . Notice that as you scroll the GridView, the header row scrolls out of view. It would be more convenient to have a locked header row so that the header row is always visible regardless...(read more)

Getting access denied error when querying for user Roles using Authorization Role Manager

2009-06-19T01:21:46Z

Recently I was working on an AuthorizationRoleProvider issue for an ASP.Net application. Customer was using Authorization Role Manager for the Role management of the Active Directory users. Scenario ======= You developed an Asp.net application using Authorization Role provider. We logged in as User1 into the application through Forms authentication. We used the following code: string role="Admin"; if (Roles.IsUserInRole(“User2”,role)) { //Do something } When we try to check if User2 is...(read more)