For spacedesk HTML5 VIEWER, no setup installation is needed on the Secondary Machine. HTML5 VIEWER operates with a standard web browser without any setup needed upfront. It can be opened directly from the website http://viewer.spacedesk.net/. 
Make sure that the web browser (e.g. Safari, Google Chrome, Opera, Internet Explorer, etc.) is updated to the latest version.
It is important to understand, that spacedesk HTML5 VIEWER does not operate over the internet. 
It does not need an internet connection. It does not even need to be opened over the internet as described above. 

The HTML5 page can be saved locally.
Local install (optional):The web page can be saved to be used off-line even without internet connection. 
Follow the instructions below:


  • Refresh using Ctrl-F5 keys after opening HTML5 page (this ensures that everything is updated). 
  • For Google Chrome browser, use the the menu “Cast, save, and share" then click on "Save page as...".
  • For Microsoft Edge, open the "..." menu, select "More tools", then click on "Save page as".