Debugging Virtual Machine using Windbg

Question

I am trying to connect to a Windows XP Professional Virtual Machine running under Microsoft Virtual PC for debugging purposes. I was following the MSDN kernel mode debugging article, however bcdedit command was not being recognized on the guest machine so I added the following entry in the boot.ini file under C:\ drive

multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="KD" /fastdetect /debug /debugport=2 /baudrate=115200

I configured the com2 port to a named pipe (\\.\pipe\pipe2)

I enter the following command at the command prompt and turned on the virtual machine

windbg -k com:pipe,port=\\.\pipe\Pipe2,resets=0,reconnect

and I get the following output

Microsoft (R) Windows Debugger Version 6.12.0002.633 X86
Copyright (c) Microsoft Corporation. All rights reserved.

Waiting for pipe \\.\pipe\pipe2
Waiting to reconnect...
Connected to Windows XP 2600 x86 compatible target at (Fri May  9 05:34:23.920 2014 (UTC + 5:30)), ptr64 FALSE
Kernel Debugger connection established.
Symbol search path is: C:\Windows\Symbols;srv*C:\Windows\Symbols*http://msdl.microsoft.com/download/symbols
Executable search path is: 
Windows XP Kernel Version 2600 UP Free x86 compatible
Built by: 2600.xpsp_sp3_qfe.100216-1510
Machine Name:
Kernel base = 0x804d7000 PsLoadedModuleList = 0x8055b1c0
System Uptime: not available
56: ERROR: UMRxReadDWORDFromTheRegistry/ZwQueryValueKey: NtStatus = c0000034
ERROR: DavReadRegistryValues/RegQueryValueExW(4). WStatus = 127
ERROR: DavReadRegistryValues/RegQueryValueExW(5). WStatus = 127
ERROR: DavReadRegistryValues/RegQueryValueExW(6). WStatus = 127

The status bar at the bottom says 'Debugee not connected'

Am I missing something?

Answer 1

It has been a while since I've used Virtual PC, but I remember the instructions in this guide worked well: http://silverstr.ufies.org/lotr0/windbg-vmware.html

However, Virtual PC is extremely outdated (7 years old) and it's much easier nowadays to do VM kernel debugging with VirtualKD along with VMware or VirtualBox.

Answer 2

that is normal for virtual pc to say debugee not connected as it has not
connectedto the target yet it has just established a transport

press ctrl+break once to connect and press g to resume running.

As Jason suggested get the free vmware player and configure virtualkd for a much
faster debugging com port is too slow for many things especially conditinal log breaks
will stall the debugger for minutes together.