Have you ever logged in to your WSUS console and received an error instead of updates? Yep, it happened to me too. When WSUS (
Windows Server Update Services) freezes on syncing, it's like your server just went dark.
Let me simplify it: if WSUS is not synching, your server will not be able to download patches. No patches equal security vulnerabilities, bugs, and hassles later on. Don't worry, though. I'll tell you what's happening and
fixing WSUS Sync issues.
What Is WSUS Sync, Really?
WSUS sync is like your server going out and looking at Microsoft for updates. It goes out, asks, "Got any new stuff?" and downloads patches.
But when sync doesn't work, it feels like your server's network connection has been dropped. It won't know what's new, and can't even do catch-up patches.
Why Does WSUS Stop Syncing?
I asked the question myself too. Here are some common reasons:
- Microsoft certificates that expired (these allow your server to trust the updates)
- Firewall or proxy issues preventing your server from accessing Microsoft
- Windows updates that cause something to break in WSUS (ah, irony)
- Broken date/time on your server (sounds ridiculous, but it counts!)
Did you ever catch your server with the incorrect year? I did—it breaks my heart!
How Do You Know WSUS Sync Is Broken?
This is what I did:
Open
WSUS and look at the sync result.
If it contains such words like "
sync failed" or "
connection error", that's your first sign.
Also, open
Event Viewer (under
Windows logs) and look for errors such as
10032 or
12072. These typically indicate sync is broken.
How Do You Fix It?
Alright, now to the good stuff. Here's what I discovered to work:
Update Security Certificates
Microsoft altered their update release process. Your server requires fresh root certificates or it will not trust Microsoft servers.
You can run this command on PowerShell:
“powershell
certutil -generateSSTFromWU roots.sst”
Then import that file (roots.sst) to Trusted Root Certificates.
Verify Firewall and Proxy Settings
Your server must connect to:
"https://update.microsoft.com
https://download.windowsupdate.com"
Test using this command:
“powershell
Invoke-WebRequest -Uri https://download.windowsupdate.com”
If it does not work, your firewall or proxy are causing it to block.
Install Most Recent Updates
Ironically, some outdated Windows updates corrupted WSUS. Ensure your server is up to date with Microsoft's newest updates.
Why You Shouldn't Ignore This
If you let WSUS become infected:
- Your servers won't receive security patches
- Your configuration will pass audits or tests
- You'll have more to do later repairing strange problems
Trust me, it's better to repair WSUS now than to have larger issues later.