Remove obsolete Win10 1903/legacy WSL sections; fix wsl --version references

* Remove obsolete Win10 1903 section and legacy WSL uninstall; fix wsl --version

- Remove 'I'm on Windows 10 version 1903' section — Win10 1903 reached
  EOL December 2020; the backport KB is no longer relevant
- Remove 'Uninstall legacy version of WSL' section — targeted Windows 10
  pre-Creators Update (Oct 2017, Build 16299), which is years past EOL
- Fix wsl.exe -v -> wsl --version in bug report template for consistency
  with current WSL documentation

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Address Copilot review feedback: wsl --version fallback, lsb_release fix, remove lxrun

- Add wsl.exe --status fallback for inbox WSL users in bug report template
  (wsl --version requires Store WSL)
- Fix 'run lsb_release -r' → 'lsb_release -r' (spurious 'run' prefix)
- Replace lxrun /setdefaultuser with wsl -u root in older-versions section
- Replace lxrun /uninstall /full with wsl --unregister in system restore section

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: GrantMeStrength

WSL/troubleshooting.md

@@ -1,7 +1,7 @@
 ---
 title: Troubleshooting Windows Subsystem for Linux
 description: Provides detailed information about common errors and issues people run into while running Linux on the Windows Subsystem for Linux. 
-ms.date: 10/03/2025
+ms.date: 04/15/2026
 ms.topic: troubleshooting-general
 ---
 
@@ -25,10 +25,10 @@ The [WSL product repo issues](https://github.com/microsoft/WSL/issues) enables y
 
   - Issue Title
   - Windows Version: Please run `cmd.exe /c ver` to get the build of Windows you are on.
-  - WSL Version: If you are running Windows Subsystem for Linux from the Microsoft Store, please run `wsl.exe -v`.
+  - WSL Version: Run `wsl --version` to get your WSL version. On older (inbox) WSL builds, run `wsl.exe --status` instead.
   - Are you using WSL 1 or WSL 2: Tell us whether the issue is on WSL 2 and/or WSL 1. You can tell by running `wsl.exe -l -v`.
   - Kernel Version: Please tell us what version of the Linux kernel you are using, or if you are using a custom kernel. You can run `wsl.exe --status` if that command is available to you, or by running `cat /proc/version` in your distro.
-  - Distro Version: Please tell us what distro you are using (if applicable). You can get additional information about the version where possible, e.g. on Debian / Ubuntu, `run lsb_release -r`.
+  - Distro Version: Please tell us what distro you are using (if applicable). You can get additional information about the version where possible, e.g. on Debian / Ubuntu, `lsb_release -r`.
   - Other Software: If you're reporting a bug involving WSL's interaction with other applications, please tell us. What applications? What versions?
   - Repro Steps: Please list out the steps to reproduce your bug.
   - Expected Behavior: What were you expecting to see? Include any relevant examples or documentation links.
@@ -105,12 +105,6 @@ You can also:
 
 ## Common issues
 
-### I'm on Windows 10 version 1903 and I still do not see options for WSL 2
-
-This is likely because your machine has not yet taken the backport for WSL 2. The simplest way to resolve this is by going to [Windows Settings](ms-settings:windowsupdate) and clicking "**Check for Updates**" to install the latest updates on your system. See [the full instructions on taking the backport](https://devblogs.microsoft.com/commandline/wsl-2-support-is-coming-to-windows-10-versions-1903-and-1909/#how-do-i-get-it).
-
-If you hit "**Check for Updates**" and still do not receive the update you can [install KB KB4566116 manually](https://catalog.update.microsoft.com/Search.aspx?q=KB4566116).
-
 ### Error: 0x1bc when `wsl --set-default-version 2`
 
 This may happen when 'Display Language' or 'System Locale' setting is not English.
@@ -690,8 +684,8 @@ sudo update-locale LANG=en_US.UTF8
 
 2. Enable the WSL optional feature (if not already)
 3. Reboot
-4. lxrun /uninstall /full
-5. Install bash
+4. Run `wsl --unregister <DistroName>` to remove the legacy WSL distribution (for older legacy WSL, `lxrun /uninstall /full` was used)
+5. Reinstall the Linux distribution from the Microsoft Store
 
 ### No internet access in WSL
 
@@ -871,11 +865,7 @@ Interoperability command differences:
 - To see what commands are available for a particular distribution, run `[distro.exe] /?`. For example, with Ubuntu: `C:\> ubuntu.exe /?`.
 - Windows path is included in the WSL `$PATH`.
 - When calling a Windows tool from a WSL distribution in an earlier version of Windows 10, you will need to specify the directory path. For example, to call the Windows Notepad app from your WSL command line, enter: `/mnt/c/Windows/System32/notepad.exe`
-- To change the default user to `root` use this command in PowerShell: `C:\> lxrun /setdefaultuser root` and then run Bash.exe to log in: `C:\> bash.exe`. Reset your password using the distributions password command: `$ passwd username` and then close the Linux command line: `$ exit`. From Windows command prompt or Powershell, reset your default user back to your normal Linux user account: `C:\> lxrun.exe /setdefaultuser username`.
-
-## Uninstall legacy version of WSL
-
-If you originally installed WSL on a version of Windows 10 prior to Creators update (Oct 2017, Build 16299), we recommend that you migrate any necessary files, data, etc. from the older Linux distribution you installed, to a newer distribution installed via the Microsoft Store. To remove the legacy distribution from your machine, run the following from a Command Line or PowerShell instance: `wsl --unregister Legacy`. You also have the option to manually remove the older legacy distribution by deleting the `%LocalAppData%\lxss\` folder (and all it's sub-contents) using Windows File Explorer or with PowerShell: `Remove-Item -Recurse $env:localappdata/lxss/`.
+- To run a command as `root` for early versions, use `C:\> bash.exe -c "su -"`. On supported Windows versions, use `wsl -u root` instead.
 
 ## Error code 0x8000FFFF unexpected failure