Under the Update & Security page click on Troubleshoot from the left-hand side. Open Windows Settings by pressing Windows + I, and click on Update & Security. Search and Indexing Troubleshooter is the inbuilt tool that is used to scan for issues on your Cortana and windows search Indexing. Mostly this error occurs due to missing system files or an issue with the Cortana application. Once you encounter this error first you restart the system once and check, and follow the below mentioned recommended solutions one by one to fix the issue. Run Search and Indexing Troubleshooter Restart the Cortana Process in Task Manager Reinstall Cortana Fix Cortana Package Folder Reinstall iCloud Perform Clean Boot Create a New User Account Check for Windows Update Run DISM tool Let’s See the topics in detail Fix SearchUI.exe missing in Windows 10: