xdk_web_mac_master_3759.dmg does not open

[David_M_1]

Any ideas why this will not open?  I'm running OSX 10.12.3 Sierra.  Please advise.  Thanks. 

[PaulF_IntelCorp]

Perhaps your Mac is configured to prevent "downloaded" apps from being installed on your system. This doc might help > http://osxdaily.com/2016/09/27/allow-apps-from-anywhere-macos-gatekeeper/ <

[David_M_1]

This is not a question of installing the app.  The .dmg file won't open - period.  I can't install the app if the file doesn't open first.  I've tried Stuffit Expander, right-click and chose Open, select file and use keys Command O, nothing happens.  

[PaulF_IntelCorp]

I've not seen this before. Try opening a terminal window and "cd" to the location of the dmg file (for example, I'm assuming it is in your Downloads folder):

$ cd ~/Downloads
$ open xdk_web_mac_master_3759.dmg

And, if that doesn't work, try this:

$ cd ~/Downloads
$ sudo open xdk_web_mac_master_3759.dmg

In the second case you'll be asked for your system's "root" password (or administrator password). But the XDK might get installed in a location that you cannot start it from. Let me know if either of these work.