Security AlertMedium
Microsoft says Windows updates are breaking SQL Server performance
Nov 12, 2026 · Summarized by Fundy Tech from 2 sources
The 30-second version
Microsoft says recent Windows updates can leave SQL Server connections open and slow systems down. It will release an out-of-band fix in the next few days.
Key points
- Affects Windows 10, Windows 11 and Windows Server 2012 and later.
- Linked server queries using OLE DB providers are affected.
- Admins may need to restart SQL or close open connections temporarily.
Why it matters
If your business runs SQL Server, performance can degrade over time and affect apps, reports, and databases. The issue can hit both client and server systems, so IT teams should watch for slowdowns and plan for a fix.
Who’s affected: Windows and SQL Server systems
What to do
- Check whether SQL Server linked server queries are affected.
- Watch for Microsoft's out-of-band Windows update.
- Contact Microsoft Support for Business if you need mitigation.
Original reporting
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