Hi musicmaster — sorry the 25H2 upgrade made your PC feel slower. The screenshot helps a lot. Quick answer first, then concrete troubleshooting and rollback options.
Short explanation of what you’re seeing in Windows Update
- The message doesn’t mean the feature update wasn’t installed. It means: the feature update (Windows 11, version 25H2) is on the PC, and Windows Update is now offering a cumulative update (KB5070773 in your screenshot) that applies to 25H2. So “25H2 is installed” and “25H2 updates are available” can both be true at the same time — one is the feature update, the other is a later cumulative/quality update for that same version.
What I recommend you do (in this order)
- Install the pending cumulative update
- Click “Downloaden en installeren” (Download and install) for the KB shown in your screenshot, reboot when prompted. Many post-upgrade performance problems are fixed by the first cumulative update after a feature upgrade.
- Check your exact installed version and build
- Press Windows key + R, type winver and press Enter. Tell me the “Version” and “OS build” lines that appear (or copy a screenshot). This confirms exactly what is installed and whether the KB was applied.
- Check Task Manager for real bottlenecks
- Open Task Manager (Ctrl+Shift+Esc) → Processes tab. Sort by CPU, Disk and Memory to see which process is using the system heavily. Also open Startup tab to disable anything unnecessary from starting.
- If you see a process using lots of disk (SearchIndexer, OneDrive, Antimalware Service, etc., tell me what it is.
- Common quick fixes to try now
- After installing the KB and rebooting, let the PC sit idle for 15–30 minutes (Windows often finishes background indexing, optimization and driver installs after an upgrade).
- Pause OneDrive sync temporarily (if you use OneDrive) while testing.
- Run a quick SFC/DISM health check:
- Open an admin Command Prompt and run:
- sfc /scannow
- DISM /Online /Cleanup-Image /RestoreHealth
- Reboot after those finish.
- Try a Clean Boot to rule out third‑party software
- Press Windows key, type msconfig → Services tab → check “Hide all Microsoft services” → click Disable all → open Task Manager → Startup tab → disable third-party startup items → Restart. Test performance. If it’s fixed, re-enable services/startup items one at a time to find the culprit.
- Check device drivers and storage health
- Open Device Manager and look for devices with yellow exclamation marks. Right-click major devices (display, storage controller, network) → Update driver or visit the vendor’s website for the latest driver.
- If you have an HDD, check Disk health (CrystalDiskInfo or built-in Manufacturer tool). If it’s an SSD, ensure firmware and TRIM are OK.
- Check whether Windows is still doing background tasks
- Indexing rebuild, SearchIndexer activity, “device optimization”, and Windows Update background installs can cause temporary slowness for several hours after a feature upgrade. Resource Monitor can show I/O waits.
If you want to roll back to the previous Windows version
- There’s a built-in rollback option for a short time after a feature update (by default 10 days).
- Settings → System → Recovery → “Go back” (or “Go back to the previous version of Windows”) — if that option is present you can use it. Follow the prompts and keep PIN/password handy.
- Important: If you used Disk Cleanup or Storage Sense and removed “Previous Windows installation(s)” (the Windows.old files), rollback won’t be available.
- If rollback isn’t available and you want to go back, the safe way is to restore from a full image backup or reinstall the old version manually (I can guide you through creating installation media and doing a reinstall if needed).
What I need from you to continue
- Tell me what winver reports (Version and OS build).
- After you install that KB and reboot, tell me whether things improved.
- If still slow: open Task Manager → Processes and report which process(es) show highest CPU/Disk usage (name and %). Also tell me whether your system disk is an SSD or HDD and approximate age/specs (CPU/RAM).
If you want, I can give step‑by‑step commands for SFC/DISM, how to use Resource Monitor, and the exact rollback/check-for-Windows.old steps. Which would you like me to provide next?
