Error: The protocol handler cannot be found. Check that the handler has been installed.

You will get this error, when you are trying to initiate the crawl from any of the content source.

Solution

1. Stop the below 3 services from Services.msc

    a) Office SharePoint Server Search

    b) Windows SharePoint Services Search

    c) Windows SharePoint Services Timer.

                   

2. Start all the 3 services again.

3. Reset the IIS