I just installed on a MSI laptop running Windows 10 Ver. 1803 with a gigabyte internet connection (960mps upload 950mps download). Every time I start up the application, it immediately displays a dialog box stating "Internet access failed" as you can see below. Clicking retry does not help as it simply pops up the same dialog box again, clicking cancel shuts the program down. Clicking ok simply allows the program to run in offline mode which is not what I want.
Quoting from Lego's LDD page:
Sorry. We don’t support LDD version 4.3.10 anymore.
If you still use version 4.3.10 you will experience errors when launching the application.
You can still use “offline” mode if you wish. We urge you to update, use the download link, and install free application for Windows PC & Mac OSX.
There is nothing wrong with your computer, or your internet connection (and it is not just you). LDD will still function normally, albeit in "offline mode."
LDD is now past its end of life, and Lego apparently does not care any longer about collecting usage data on LDD.
The "Internet access failed" message is because LDD can no longer reach a Lego server (184.108.40.206). LDD "phoned home" every time it was started. Now because it can not reach its home server LDD generates this "Internet access failed" message and will only run in offline mode. Apart from spoofing the replies LDD is looking for there is no way to run LDD in online mode any longer.
However, seeing as how Lego shut down the DesignByMe service you are not missing much (if anything) by running LDD in offline mode.
You still can get LDD 4.3.11 which has a problem with Adobe Flash Player during the installation procedure.
Luckily, these thread explain the fix. I've replicated their instructions and I've managed to get 4.3.11 working with all the newly incorporated parts, with a few cmd.exe commands that only took two minutes.
Basically the installation process pauses when you are asked to install Flash Player (no longer available for download as of 12 Jan 2021 - its EOL). But technically, LDD doesn't even need it, as it can run fine with OpenGL. So at the installation step when you get the prompt to Install Flash Player, DON'T click "YES" just yet. Follow these steps instead:
run cmd.exe in your Windows search bar.
Navigate to the temporary installation folder by typing this into the command line:
You should see the file named install_flash_player_active_x.exe. Rename that to something else:
rename install_flash_player_active_x.exe alt.exe
Rename the file OpenGLChecker.exe to install_flash_player_active_x.exe:
rename OpenGLChecker.exe install_flash_player_active_x.exe
Proceed with the LDD installation by clicking "YES". Now the installer should skip the step where it attempts to install Flash Player.
Hope this helps!