Overview

Although search crawlers may be enabled/disabled via the UI, it's also possible to do so via SQL query. The following steps will guide you in doing that. 

Steps

Requirements: Access to run queries on the DNN SQL server

1. Log in to SQL Server Management Studio.

2. In the left side Object Explorer, Double click on your server name and then Databases to expand. 

3. Find your DNN database and right-click to select New Query. 

4. Execute the following queries to enable the crawlers:

UPDATE Schedule
SET Enabled = 1
WHERE TypeFullName = 'DotNetNuke.Professional.SearchCrawler.FileCrawler.FileCrawler, DotNetNuke.Professional.SearchCrawler';

UPDATE Schedule
SET Enabled = 1
WHERE TypeFullName = 'DotNetNuke.Services.Search.SearchEngineScheduler, DOTNETNUKE';

UPDATE Schedule
SET Enabled = 1
WHERE TypeFullName = 'DotNetNuke.Professional.SearchCrawler.SearchSpider.SearchSpider, DotNetNuke.Professional.SearchCrawler';

NOTE: In order to disable the crawlers, run the queries above but replace "SET Enabled = 1" with "SET Enabled = 0"

5. Validate the change by logging in to your DNN instance with SuperUser credentials and going to Persona Bar > Settings > Schedulers. If successful, you will see the appropriate status reflected next to the entries for the crawlers (check mark for enabled, no check mark for disabled).