Troubleshooting Windows Update has seemingly become a forced-favorite pastime for some responsible for ensuring that the organization is current for the latest patches. Despite its simplicity (check for patch, download patch, install patch), Windows Update itself can run into problems. In the past, Microsoft provided a special %windir%\Windowsupdate.log file to sift through and locate error and warning messages to use to fix issues.
In Windows 10, Microsoft has decided to change how this works. I outlined the difference exhibited in Build 9926 of Windows 10 in Windows Update Logging Change in Windows 10 Build 9926. When you open the old %windir%\Windowsupdate.log file on Build 9926, it contains a simple message:
Even though Microsoft provided a link in the text to guidance for how to troubleshoot Windows Update in Windows 10, the link wasn't yet valid. The full KB Article is now available, but you might not be happy with it because it makes troubleshooting a bit more difficult.
Microsoft states the change is to help with performance and to reduce disk space usage, which makes sense, considering Windows 10 will be a single code base that can install on any computer or device – including those with minimal storage. Windows 10 now uses Event Tracing for Windows (ETW) for generating logs for Windows Update, but that means that the logs are not immediately readable. To be able to read the logs you have to download a couple things, public symbols and the Tracefmt.exe tool. Once you have the downloads you run through a series of steps (outlined in KB Article 3036646), including creating a temporary folder in which to house both the Tracefmt.exe tool and the unreadable log files, and the run a command-line.
Let's hope this is a temporary solution to troubleshooting Windows Update and that Microsoft is working on a simpler method.