If internet feels slow after a Windows update, first check whether an update or another app is still transferring data. Then compare the laptop with another device and, where practical, Ethernet. A slowdown that follows an update is a useful clue, but it does not establish that the update changed your driver or TCP settings.
Start with the pattern, then choose a check
| What you observe | Useful next step | Keep in mind |
|---|---|---|
| Every device slows down during an update download | Compare after the transfer finishes; review Delivery Optimization activity. | Shared traffic can affect other devices without a driver fault. |
| Only the updated PC is slow on Wi-Fi | Compare Ethernet or the same Wi-Fi location and review its supported adapter driver. | A second device is a comparison, not a matched hardware test. |
| Only one browser or app is affected | Compare another app and review its own diagnostics. | A browser or app problem does not establish a whole-connection capacity loss. |
| The PC cannot connect at all | Use Microsoft’s connection troubleshooter and check the adapter. | A throughput test needs a working connection and cannot inspect adapter settings. |
1. Record the problem before changing settings
Note the Windows build, network adapter model and driver version, connection type, time, and the app affected. Run a quiet-network speed test and keep the result. A browser result cannot inspect Windows Update or identify which process is transferring data.
2. Check active transfers
Open Task Manager and look at the Network activity of processes you recognise. Check Windows Update for ongoing work and allow required updates to complete. Pause an optional cloud backup or game download for one comparison; do not end an unfamiliar system process just because its name appears in the list.
3. Review Delivery Optimization controls
Microsoft documents Windows 11 controls under Settings → Windows Update → Advanced options → Delivery Optimization. The available page can vary by build and organisational policy. Review its activity and sharing settings before deciding whether to adjust a limit.
The documented bandwidth limits apply to automatic update downloads handled by Delivery Optimization. They do not govern every transfer: Microsoft specifically excludes manually initiated Windows or Store downloads from those automatic-update limits. Turning off sharing with other PCs also does not turn off Windows updates.
4. Compare Wi-Fi with a second connection
If only this laptop is affected, compare it near the router and on Ethernet if available. Use the Wi-Fi room comparison to keep location and device consistent. If other devices slow down at the same time, investigate shared traffic or the internet connection as well.
5. Check the supported adapter driver
Compare the installed driver with the computer or adapter manufacturer’s support information. If the timing points to a driver change, use its documented update or recovery procedure and record the original version. A recovery option may not be available on every system. Avoid third-party driver-download sites.
6. Separate browser, app, and filtering issues
Compare another browser or one ordinary download without changing several conditions at once. Keep security protection enabled and follow the vendor’s guidance if filtering software appears involved. A changed DNS resolver is not a general way to increase download capacity, and registry or TCP tuning should not be the first response to an unexplained result.
7. Keep the comparison that explains the symptom
Repeat the original check after one adjustment. If calls become delayed only while updates transfer data, compare idle and loaded browser timing with the bufferbloat test. If a meeting alone is the problem, try the video-call connection check and the app’s own diagnostics. Neither web tool certifies a Windows process or live-call route.
Share the build, driver version, timestamps, and before/after observations with the device maker or IT team if the fault persists. On a managed PC, ask the administrator before altering required network settings.
Use network reset only after narrower checks
Microsoft treats network reset as a late troubleshooting step. On Windows 11, its documented route is Settings → Network & internet → Advanced network settings → Network reset. It removes installed network adapters and their settings, then reinstalls adapters after a restart. VPN software or virtual switches may need setting up again, and known networks can return as public profiles. Read Microsoft’s full instructions and ask IT before using it on a managed PC.
A short record for support
Keep four items together: the Windows build and driver version; the app and connection affected; results before and after one change; and whether another device showed the same symptom at the same time. Record failed or interrupted tests explicitly. Repeated observations are more useful than a single best speed-test number.
Frequently asked questions
Should I uninstall the update immediately?
Not solely because one speed test is lower. First identify whether a transfer, device-specific connection issue, or application fault explains the change. Follow Microsoft or the device maker’s current recovery guidance if a specific regression is confirmed.
Does flushing DNS make downloads faster?
It can address some name-resolution problems. It is not evidence that a connection’s bulk transfer capacity will improve.