When you open the Indexing Options applet, the Modify, Advanced, and Pause buttons remain grayed out. Also, the message Waiting to receive indexing may be shown in the Indexing Options dialog, even though the Windows Search service is already running.
This happens if the index catalog is corrupted. To fix the problem, force a repair of the search index catalog using these steps:
Note: The following procedure also resets the indexed locations list to defaults. After following the procedure below, you’ll need to manually add your preferred location(s), by clicking the Modify button. For more information, read the Indexing Options FAQ How do I add new files or locations to the index?
1. Click Start, type regedit.exe and press ENTER
2. Navigate to the following branch:
HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows Search
3. Double-click SetupCompletedSuccessfully and set 0 as its Value data
4. Exit the Registry Editor
5. Restart Windows.
After the restart, the corrupted index catalog is rebuilt from the scratch. Indexing can take a long time to complete.