Why "Azure" related tools are grey out in SSIS after installation of Azure feature pack?

Problem: After installation of Azure feature pack for SSIS, Azure related toolboxes are still grey out?

Solution: 

If Azure related toolboxes are grey out in SSIS, that means that the version of SQL server is different from the version of Azure feature pack. You need to change the TargetServerVersion in visual studio to the same version of Azure feature pack you installed.

For example, if you download and install Microsoft SQL Server 2016 Integration Services Feature Pack for Azure for SQL Server 2016, you need to set TargetServerVersion in visual studio to be SQL Server 2016 as shown below:

Now your project version will show: SQL Server 2016 and Azure related tools will show up in your SSIS toolbox!