Installation of Microsoft SQL Server Data Tools Hangs I'm attempting to install SQL Server Data Tools, but the installation is hanging.  It had an error the first attempt; and I've restarted the machine (as that seems to help in those scenarios).  Now it just sits there on the tools for Visual Studio not installing (I've left it running over night).  Any suggestions on what to do here?
I experienced exactly the same error, right down to the pixel.  I figured out the solution by continuing the broken installation using the standard VS 2017 installer (it will recognize that the SSDT installer error'd out).  Resuming this installer reported more information via error logs.  The errors were folder/file access permissions being restricted by McAfee Anti-virus

tldr; disable your anti-virus.