1. Knowledge Base Article
Page 1 of 2
Created On: 13-Dec-2013
Author: Eric Roberson
Title
About Windows Update Verbose Logging
Description of Issue
 This solution explains how to enable and interpret Windows Update
verbose log files.
 Information in this solution applies to computers running Windows 7.
Description of Resolution
WARNING: Incorrect use of the registry editor can cause computers to
malfunction and may lead to catastrophic data loss. Be sure to backup the
Windows registry before making any changes.
Part 1: Enable Windows Update Verbose Logging
1. Log into the computer using an account with elevated privileges.
2. Click Start > Run, then type regedit. Press Enter.
3. Browse to HKLMSOFTWAREMicrosoftWindowsCurrentVersion
WindowsUpdate. Create a new hive called Trace.
4. Under HKLMSOFTWAREMicrosoftWindowsCurrentVersion
WindowsUpdateTrace, create each of the following dword values:
 Flags = 00000007
 Level = 00000004
5. Exit the registry, then restart the computer.
6. Allow Windows Update time to install updates before interpreting the
log.
Part 2: Interpret the Log File
1. If necessary, copy server_nameshare_name$cmtrace.exe to
C:localdocs. Double click cmtrace.exe, then click OK to accept the
change.
2. Click Start > Run, then type windowsupdate.log. Press Enter.
3. To find failures in the log, click Tools > Find, then type fatal or
warning in the search field. Click OK.
4. Or, scroll through the log file. Search for any lines highlighted in red
or yellow. These highlights usually indicate problems with an update
or installation.

2. Knowledge Base Article
Page 2 of 2
Part 3: Disable Windows Update Verbose Logging
1. Log into the computer using an account with elevated privileges.
2. Click Start > Run, then type regedit.
3. Browse to HKLMSOFTWAREMicrosoftWindowsCurrentVersion
WindowsUpdateTrace. Set each of the following dword values to
zero:
 Flags = 0
 Level = 0
4. Exit the registry, then restart the computer.
5. Verbose logging is now disabled.
Additional Information
For more information, see “How to Read the Windowsupdate.log File” at
http://support.microsoft.com/kb/902093 .
Revision History
Revision Number Date Editor Summary of revision
0.1 13-Dec-2013 Eric Roberson Draft
Tags
WSUS; Log; Verbose