I had to install VSD on another computer today, but it won't install.

It says that I do not have authority to make the installation changes.

I tried installing as the administrator, dl the software as the administrator but it won't install.

Which operative system are you running? And are you trying to install VSD to the default location or somewhere else on your system?

Are you the admin on that computer, or a 'Limited user'?
What kind of error messages do you get?

You have to share a bit more information in order to help us help you.