How to Fix the Annoying WSL "Press any key to install" Popup on Windows 11 (After Uninstalling WSL)

The persistent WSL installation prompt appearing after uninstalling WSL is caused by the P9RdrService. This service, part of WSL's file-sharing mechanisms, remains active even after WSL removal. When the P9RdrService starts, it tries to connect with nonexistent WSL components, leading to the update prompt. To resolve this, disable the P9RdrService in the Services GUI or using PowerShell as an administrator. The P9RdrService attempts to initiate a connection with WSL, prompting for an update. This problem occurs despite the uninstallation of WSL, removal of distros, and disabling the WSL feature. Process Monitor, a Sysinternals tool, aids in finding the root of the problem by identifying the wsl.exe process. Boot logging is necessary to capture this because the prompt appears during boot before manual operation. Filtering the logs reveals svchost.exe launching wsl.exe, which further pinpoints the responsible service. Examining the svchost.exe command line reveals the culprit is the P9RdrService. Prior attempts at fixing the issue, like removing WSL features and terminal profiles, had failed. Removing the WSL AppX package didn't solve it either. No WSL related entries were found in the startup apps or the Task Scheduler. The solution is to disable the P9RdrService, and after a reboot, the pesky prompt disappears.