Most devices will provide the download link automatically when you first log in to their web interface.
If you are prompted to download Webplugin.exe , how do you know if it is safe? Follow the : Webplugin.exe Download
If you genuinely need the legitimate version (for ALSee or a legacy tool), follow these – never use a random "DLL download" or "EXE download" site. Most devices will provide the download link automatically