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Windows troubleshooting guides

Diagnose Windows virtualization, shared folders, devices and recovery issues with prerequisites, specific steps and official Microsoft sources.

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▦Gaming monitor OSD settingsTroubleshooting guide

Monitor shows "No Signal" after changing OSD overclock or DisplayPort settings: how to get the picture back

Right after turning on overclocking or raising the maximum refresh rate in the monitor OSD, the monitor shows "No Signal" or the screen stays black

Windows 11 / Windows 10. The screen shows "No Signal" or stays black right after you changed overclocking (a higher maximum refresh rate) or the DisplayPort version setting in the monitor's on-screen menu (OSD), or after adding a custom resolution in the graphics driver
Checked 2026.09.13Read guide ↗
▦M.2 NVMe SSDTroubleshooting guide

Large copies to an NVMe SSD slow down partway: tell thermal throttling from write cache limits and check cooling

A large copy to an NVMe SSD starts fast, then the transfer speed drops sharply partway and either stays low or keeps rising and falling

M.2 NVMe SSDs installed in Windows 11 / Windows 10 desktop or laptop PCs where copying or exporting files of tens of gigabytes or more, such as games or video, starts fast and then drops sharply partway through
Checked 2026.09.13Read guide ↗
▦USB external SSD / M.2 SSD enclosureTroubleshooting guide

External SSD not reaching USB 20Gbps or USB4 speed: check PC ports, cables, hubs and Windows indicators

A USB 20Gbps or USB4 external SSD copies large files far below the maximum speed on its product page, no faster than a 10Gbps or 5Gbps product

Windows 11 / Windows 10 desktop or laptop PCs with a USB 20Gbps (USB 3.2 Gen 2x2), USB 40Gbps (USB4) or Thunderbolt external SSD or M.2 SSD enclosure attached, where transfers never reach the product's advertised speed and stay at 10Gbps or 5Gbps levels or lower
Checked 2026.09.13Read guide ↗
▦Inkjet / laser printer (Brother, Epson)Troubleshooting guide

Printer outputs blank pages after an ink or toner change: packing material, seating, nozzle check and the new-supply test

Every page comes out completely blank right after a new ink or toner cartridge was installed

Pages come out completely blank, or one or more colors are missing, immediately after replacing an ink cartridge, ink bottle, toner cartridge or drum unit (worked through the published procedures for Brother inkjet and laser machines and Epson inkjet printers, which follow the same order on other makes)
Checked 2026.09.19Read guide ↗
▦Windows 11 power mode / energy saver, laptop maker power profiles (Lenovo Intelligent Cooling)Troubleshooting guide

Laptop is slow only on battery: check the power mode, energy saver and the maker's cooling mode in that order

The same work becomes slower the moment the power adapter is unplugged: lower frame rates, longer exports, sluggish response

Windows 11 (energy saver on 24H2 and later, battery saver on 24H1 and earlier and on Windows 10). Lenovo ThinkPad Intelligent Cooling user guides are used as the published example of the maker side
Checked 2026.09.19Read guide ↗
▦Windows 11 / Windows 10 external USB storage (removal policy, write caching, USB selective suspend), bus-powered and self-powered USB hubsTroubleshooting guide

External drive disconnects in the middle of a large copy: check power delivery, the removal policy and USB power management in that order

An external HDD or SSD vanishes partway through a multi-gigabyte copy or backup, and File Explorer stops the copy with an error such as the device being unreachable

Windows 11 / Windows 10 (the default removal policy is Quick removal from Windows 10 version 1809 onwards). For the power-delivery side, Buffalo’s published explanation of self-powered and bus-powered USB hubs is used (published 2015-12-10, updated 2017-05-19; the figures are for USB 2.0 hubs)
Checked 2026.09.19Read guide ↗
▦PCs whose WinRE (Windows Recovery Environment) is serviced through Windows Update, on the versions KB5028997 lists under Applies ToTroubleshooting guide

Only the WinRE update keeps failing: confirm event ID 4502 before you touch the recovery partition

The same update fails over and over in Windows Update, and retrying only adds another failure to the history

KB5028997 lists Windows 10 (version 1607, 21H2, 22H2 and others), Windows 11 version 21H2, 22H2 and 23H2, and Windows Server 2016 / 2019 under Applies To (page read on 2026-09-20). Microsoft does not state that the same procedure applies to versions that are not on that list.
Checked 2026.09.21Read guide ↗
▦Windows 11 and Windows 10 PCs showing a connection notification after something is plugged into a USB-C port: a device, a dock, a display or a chargerTroubleshooting guide

USB-C connection notifications: is the port, the cable, the device or the power the missing piece?

A notification such as USB device functionality might be limited appears as soon as something is plugged into USB-C

Microsoft's support page carries steps for both Windows 11 and Windows 10, where the notification setting lives in different places. Eleven notifications are listed, and Microsoft does not state that the same explanation applies to wording that is not on the page. The page was read on 2026-09-21.
Checked 2026.09.21Read guide ↗
▦Windows 11 and Windows 10 PCs with memory integrity (core isolation) on in Windows Security, or where turning memory integrity on reports incompatible driversTroubleshooting guide

A driver can't load on this device: what memory integrity is blocking, and the choices that leaves

A notification says a driver can't load on this device, without naming the hardware

Microsoft's support pages cover the meaning of the notification, why memory integrity ends up turned off, and the four hardware security capability messages shown on the Device security page in Windows Security. No build-specific differences are given. The pages were read on 2026-09-21.
Checked 2026.09.21Read guide ↗
▦A Windows 11 or Windows 10 PC with a built-in display. On a setup with only an external monitor, the Windows brightness slider itself may not appearTroubleshooting guide

The screen brightness changes on its own: telling content-based adjustment apart from ambient-light adjustment

Brightness and contrast shift on their own when a video moves from a dark scene to a bright one

Microsoft's support page covers changing brightness manually, changing it automatically with the lighting conditions, changing it automatically with the displayed content (on some Windows 11 PCs), and the limits on night light. The content-based setting has three options. No build-specific differences are given. The page was read on 2026-09-21.
Checked 2026.09.21Read guide ↗
▦A Windows 11 or Windows 10 PC. The settings concerned are under Settings > Privacy & security > Search. On a Copilot+ PC, semantic indexing is additionally on by defaultTroubleshooting guide

A saved file does not come up in search: check what the index covers, and how deeply

A file does not appear in the results even when its name is typed exactly

Microsoft's support page covers the two indexing modes, Classic and Enhanced, the locations each covers by default, the per-file-type choice between indexing properties only and properties with content, a rule of thumb for index size, how long the first run takes, and semantic indexing and language handling on Copilot+ PCs. No build-specific differences are given. The page was read on 2026-09-21.
Checked 2026.09.21Read guide ↗
▦WindowsResolved

PC Reset or Recovery Fails After KB5063875

Settings > System > Recovery > Reset this PC fails

Windows 11 23H2/22H2 (Targeted by KB5066189 in this record. The same symptoms were also reported in other Windows 10 and LTSC editions, but the corrective update to be applied differs depending on the OS)KB5063875
Checked 2026.09.05Read guide ↗
▦WindowsResolved

Microsoft Changjie IME Input Fails After KB5062552

Unable to create or select a word after entering a complete character structure

Windows 11 23H2 and Windows 11 22H2 Enterprise/Education after KB5062552. The KB5062663 preview fix is listed for 23H2; do not install that package on 22H2 or another Windows version.KB5062552
Checked 2026.09.06Read guide ↗
▦Microsoft Defender Antivirus on WindowsInvestigating

False “Microsoft Defender Antivirus Is Disabled” Notification

"Microsoft Defender Antivirus is turned off" notification appears when starting or using Windows

Windows 11 26H1/25H2/24H2/23H2, Windows 10 22H2/21H2/LTSC 2019/LTSC 2016, and Windows Server 2025/2022/2019/2016/2012 R2/2012 with the latest Defender updates
Checked 2026.09.05Read guide ↗
▦Windows 11 / .NET Framework 3.5Troubleshooting guide

Enabling .NET Framework 3.5 fails with 0x800F081F

.NET Framework 3.5 cannot be enabled in Windows Features

Windows 11 25H2 and earlier. Windows 11 26H1 (build 28000) and later use a standalone installation method and are outside this scope0x800F081F
Checked 2026.09.05Read guide ↗