You need to differentiate between two types of machine:

1- Windows 9x/Me/XP Home type installations:

For each of these machines, please download and install our self-contained installation program TightVNC + Zebedee: https://download.pointdev.com/free/IA_TightVNC_Zebedee.exe.
These operating systems don't let you install things over the network.

2- Windows NT/W2K/W2K3/XP Pro/Vista/7/8/10/2012/2016 type installations:

The server half of TightVNC will be installed on these machines the first time you take control of them remotely via our software interfacte (IDEAL Administration or IDEAL Remote). This needs to have admin privileges on the remote stations or servers. Just answer Yes when the dialog box asks you if you want it installed.