Troubleshooting WSUS downloads

Monday and Tuesday we talked briefly about some basic troubleshooting steps for WSUS setup and synchronization, and today I’m going to talk about troubleshooting downloads. When troubleshooting downloads to the WSUS server, WSUS sends a requests to BITS to download the patches to the WSUS local update folder (if it’s configured to download to a local storage).

If on the WSUS console the download stays at 0 MB and you have patches needed for downloads, we’ll need to check the software distribution log and the event viewer to see if we can find any clues as to why the BITS download is failing.

There are a couple logs you could look at but the best resource will be softwaredistribution.log which can be found in C:program filesupdate serviceslogfiles. Simply review the log and look for any errors relating to BITS. If you find any then that’s the issue you’ll want to be troubleshooting.

Another good resource will be the Event Viewer. Typically you’ll see event IDs 386 and 364 describing synchronization failures and the most probable cause of the failure. With that said, the most common problem relating to downloading patches to the local WSUS will be related to the firewall configuration. For more information on this see:




Also make sure you have network service and user permissions on the local storage folder, <drive letter>:WSUSWSUSCONTENT. If you’re unsure you can use Process Monitor to check for access denied errors on this folder as well as to verify write permissions to the local content folder.

When files are missing on the content directory, to make sure the information on the WSUS database is consistent with the content for the patches you can issue a wsusutil reset . This command will check whether the patches approved have their updates downloaded. If the binary for the patch is not there, it will generate a BITS request to download the patch again.


That should get you started on troubleshooting any potential download issues and tomorrow I’ll post some tips on troubleshooting clients.

Joao Madureira | WSUS Support Engineer