This article only applies to .NET Framework 2.0 SP2, the .NET Framework 3.0 SP2, and the .NET Framework 3.5 SP1, when used with Windows 2003. I got several cases related to dual branch servicing model during the past months. The customers may ask: 1. My system.web.dll version is newer than the...

This is an ASP.Net application running on IIS 7. The application hangs with 50% CPU every time making a change to web.config. C ustomer has to restart IIS services to resolve the problem. Changing web.config during application running is not a good idea since this triggers application domain recycle...

Today we’ll talk a little about how to optimize state management when coding your ASP.NET application. I believe most of ASP.NET developers more or less have some knowledge of using state in ASP.NET. In this article, we’ll not be focusing on how to use state in ASP.NET but how to more efficiently...

In case you need to create multiple WF 3.5/3.0 WorkflowRuntime objects, you may find the memory usage of the workflow application keep rising (memory leak) although you have disposed the objects. To completely release the resource of WorkflowRuntime, we need to call StopRuntime method before it...

When multiple .NET runtime are loaded in one target process or one dump file, for example: 0:030> lm start end module name 00000000`1b6d0000 00000000`1b9ba000 System_Data (deferred) … 000007fe`f3e60000 000007fe`f47c5000 clr (deferred) … 000007fe`f9880000 000007fe...

Customer has an ASP.Net application uses XmlSerializer. The XML serialization infrastructure dynamically generates assemblies(by calling CSC.EXE) to serialize and deserialize specified types. By default, the assemblies will be created under %TEMP%. The file name is random generated by CSC to avoid conflict...

When .NET application highly relies on EnterpriseService Component, to avoid Performance issue, we must strictly follow below guidelines: 1. Always Call Dispose 2. If You Call COM Components, Consider Calling ReleaseComObject For details, please refer to: http://www.guidanceshare.com...

1. .NET application may crash when calling function from native C++ dll 2. DllCanUnloadNow function isn't invoked after using classic COM components in .NET applications 3. How to run .NET component in a singleuse way 4. How to invoke 64bit native COM from 32bit .Net application

1. Performance Issue Caused by Crashed Finalizer Thread 2. Deadlock due to two versions of same assemblies loaded 3. Identify deadlock through the hwnd handler

1. ASP.NET application 100% CPU caused by System.Collections.Generic.Dictionary 2. Problem on Updating ASP.NET Web Content in Failover Cluster 3. High CPU usage for .NET 1.1 XSL transformation 4. ASP.NET application high CPU utilization caused by “System.NotSupportedException...

1. TlsAlloc failed with TLS_OUT_OF_INDEXES 2. Web Application Memory leakage caused by XML operations - GetElementsByTagName() 3. Web Application Memory Leakage Caused by BSTR 4. Maxconnection failed to take effect

In a production environment, if customer sets Exchange OWA (Outlook Web Access) behind some external portal, after sign in the web portal, when access the OWA, most users don’t like re-type user name and password. We call this requirement as OWA SSO (Single Sign-on). To achieve this goal, if the...

Symptom =========== Customer built an ASP.NET web application using Visual Studio 2008 on Windows 2008. In the source code, it called a function which was imported from native c++ dll: [The source code looks like below] public partial class _Default : System.Web.UI.Page { protected...

COM Interop is a technic for calling an unmanaged COM component from a .NET application, please refer to http://msdn.microsoft.com/en-us/magazine/dvdarchive/cc163494.aspx to learn how to implement it. DllCanUnloadNow is an important function which should be implemented and exported by the COM component...

Symptom: According to the dump file, there are dozens of application domains for one asp.net web application. Troubleshooting: Asp.net starts new appdomain and unloads old one in various scenarios, for example: · Machine.Config, Web.Config or Global.asax are modified · The bin directory...

In my previous post, I give one sample on how to use Powershell to filter and categorize information from thousands of IIS7 FREB log files . Here is another sample to quickly find out useful information from .NET fusion log with PowerShell. Here we go: Problem Description ============...

Symptom: When we use svcutil.exe to generate the proxy class or configuration file through retrieving published WCF service metadata, or we add service reference in IDE to reference to a WCF service, we may receive below error message. “There is an error in the XML document. The maximum nametable...

One customer has a DCOM application, which was developed by unmanaged C++. The client application is the managed code. When the client application is compiled as a Debug version, everything runs smoothly, however, after it runs as a Release version, an “RPC is Unavailable” happens always. Analysis...

When you make calls to Web services from an ASP.NET application, you may experience contention, poor performance, and deadlocks. Clients may report that requests stop responding (or "hang") or take a very long time to execute. One very common cause is the maxconnection parameter that the System.Net...

In .NET 1.1, XSL transformation with System.Xml.XmlDataDocument may run very slowly and the CPU usage may reach 100% if you transform large data. Repro Code 1. XSL file <?xml version="1.0" encoding="ISO-8859-1"?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999...

We can set SingleUse for public classes in VB6 when creating VB ActiveX component , so that each interface call will raise new process to handle the request. Some customer would like to know how to implement in managed code. Previously, an ActiveX EXE project in VB6 can define one or more SingleUse...

Symptoms: IIS Manager hangs up on the loading procedure after the OS upgraded from Windows 2000 to Windows 2003. Customer could open IIS Manager but found it hang when right click any item on the left pane. Meanwhile, customer could still browse web pages from the clients. Analysis: ...

Recently, we got an issue from customer. They have a 32bit .Net application and use AdminIndexServer object to manage Indexing Service. Bellow error reported when running this application on 64bit Windows as there is no 32bit Indexing Service Admin Object on 64bit Windows. Retrieving the COM class...

Symptom ============= In ASP.NET web application, if you do a lot of GetElementsByTagName() operations with an XML document which is stored in ASP.NET Application state, the CLR memory usage will continuously increase and finally leads to OOM(Out Of Memory). Root Cause ============= ...

In .NET Framework 2.0, System.Net has a new feature called Tracing. System.Net Tracing is very useful for some special scenarions: - Client and server are on the same machine, in case of this network monitor doesn’t work for you as it can’t capture the loop back traffic. - Secure communication...