The DataSourceID of 'TopNavigationMenu' must be the ID of a control of type IHierarchicalDataSource

Scenario:
We installed a new solution and now when we navigate to our site collection, it simply throws this error.

The DataSourceID of 'TopNavigationMenu' must be the ID of a control of type IHierarchicalDataSource. A control with ID 'topSiteMap' could not be found.

Solution:
While I didn't really got a change to debug the real cause, I thought of sharing what I did to fix it

1. Navigate to web application folder , usually it is @ c:\inetpub\wwwroot\wss\virtualdirectories\80

2. Look for the last backed up web.config [ IIS automatically backs' up web.config files before any change.

3. Restore this web.config

That's all and it worked.