After installing Visual Studio Professional 2015 (using an RTM executable but selecting Update 2 during the setup process), I get the following warning:
Eve
In my case, it was because my internet was restricted. I had to download off-line copies of Visual Studio for SQL and SSDT. The instructions below, however, are for Visual Studio 2017.
SSDT-Setup-ENU.exe /layout <folder name>
vs_SQL.exe --layout <different folder name>
(this takes a while, it's laying out ~4 GB)<different folder name>\vs_setup.exe --wait --nickname "SSDT" --passive
<folder name>\SSDT-Setup-ENU.exe
Notes: For #2, yes it's "15" even though you're downloading Visual Studio 17. I think it ha to do with Visual Studio 2017 being at version 15 and Visual Studio 2015 being at version 17.
References:
I got the same "Hash value incorrect" error issue when i was trying to install Visual Studio 2015 Enterprise from a shared location. It got solved for me, when its installation started from from the local copy of the folder.
I.e. I have copied the setup files/packages into local drive and initiated.