Windows 10 Start menu search takes forever to return results

Since rebuilding the index did not help and the search box sometimes stays blank, the search interface itself may be getting stuck. Start menu search also loads online content, so the index is not the only possible cause.

Try these next:

1. Restart the search interface. Open Task Manager, select Details, find SearchApp.exe or SearchUI.exe, right-click it and choose End task. Open Start search again; Windows should restart the process automatically. This is separate from restarting the Windows Search service.
2. Test without an internet connection. Temporarily disconnect Wi-Fi or Ethernet and search for a built-in app such as Notepad. If results become much faster, reconnect and test a different network. That points toward the online part of search or a network timeout.
3. Test another Windows user account. Create a temporary local account under Settings > Accounts > Family & other users, sign into it, and search for Notepad. If it works normally, the problem is likely specific to your original profile.
4. If both accounts are affected, check Windows system files. Open Command Prompt as administrator and run these commands in order, letting each finish:DISM.exe /Online /Cleanup-Image /RestoreHealth sfc /scannowRestart afterward and test again.

Searching for the same built-in app at each step makes the comparison useful. There is little benefit in rebuilding the index again unless file-search results specifically point to an indexing problem.