Tools for Your Debugging Toolbox

This article was just updated to include an internal Microsoft tool that is now public. There are many free tools used to troubleshoot and debug software. Below I present a list of the tools that my peers and I use most of the time. Though most of the tools below are free Microsoft tools, not…


New Debugging Book – Windows Debugging Notebook: Essential User Space WinDbg Commands

A reference book for technical support and escalation engineers troubleshooting and debugging complex software issues. The book is also invaluable for software maintenance and development engineers debugging Windows applications and services.   Do you want to know more about this book? Check out here…


PSSCOR2, the Superset of SOS.DLL is Now Public!!!

Whenever I’m debugging with customers watching it’s inevitable: they always ask me what this PSSCOR2.dll extension is. The next question is always if PSSCOR2.DLL is going to be public. PSSCOR2.DLL is a superset of SOS.DLL and has much more commands and variations! The good news is that yes, now PSSCOR2.DLL is public, so you can download…


Special Command—Using .dump/.dumpcab to Get Dumps and Symbols from Production Servers

Using WinDbg you can create a dump file from an application running, for instance, in a production server. After collecting the dump file, you can load it in another machine and debug it. However, to be more effective during your debugging session you need symbols. Thus, thinking about it, here’s the trick to get both dump…


Special Command—Using !for_each_frame to Run Commands

!for_each_frame is a favorite among debuggers. It’s a very flexible and powerful command that enables you to run commands for each frame of the call stack. You can use basically any command.  For instance, let’s say you want to see all local variables from each frame of a specific stack. Of course, to see local variables…


Special Command—CPU Time for Each Thread with !runaway

This is one of my favorite commands! !runaway displays information about the CPU time consumed by each thread in User Mode and  Kernel Mode. It is one of those commands you run when you think the application is hung with low or high CPU or has some kind of performance issue.   Parameters: Bit 0…


[PowerShell Script] Statistics from .NET Applications

This script is more a template to show you how to use PowerDbg. I must say the idea is from my teammate Aaron Barth! This script collects information from all threads running managed code and gives the user statistics by threads like:   –      CLR stack. –      Managed objects from the stack. –      ASP.NET page….


Special Command—Parsing Strings, Files, and Commands Output Using .foreach

  This is by far one of the most powerful WinDbg commands. Even if you don’t create scripts, you’ll benefit from this command.  It’s powerful because it’s flexible. You can use it for a huge variety of operations.   The .foreach token parses the output of one or more debugger commands and uses each value…


Special Command—Parsing Commands Using .shell

Finally I’m writing about this command. I love it! It’s so powerful! .shell command launches a shell process and redirects its output to the debugger or to a specified file. Usage: .shell [Options] [ShellCommand] .shell -i InFile [-o OutFile [-e ErrFile]] [Options] ShellCommand  According to the WinDbg help, options can be: -ci “Commands” Processes the specified debugger commands and then passes their output as an…


[WinDbg Script] Displaying Queries/Stored Procedures from Threads Running Managed Code

There’s another script that gives you all queries/stored procedures from SQL Server or Oracle that are stored in the managed heap. This script is more specific because it gives you the query/stored procedure running in a specific thread. It has the option to scan all threads and to display the queries/sp for each thread.  …