>HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\Windows Search Fix Advanced Outlook Search grayed out problem via Registry Outlook again by ticking the box beside it. To move forward, tap the Modify button below then select Microsoft After that, click on Indexing Options, then select Microsoft Outlook. The first step here is to navigate to Outlook Options via the program itself the hit the Search tab situated in the left-pane. Try these: 1. Fix Outlook Search not working via Outlook Options After reading your problem, I have mentioned few methods.