Hello. Many years ago I had bought a new laptop and installed Sonar 8.5.3 on it, which I also had on my main desktop. I had many third party plugins to install / authorize. A ton of freeware and a bunch I'm embarrassed by how much I paid for back then. 

I posted here about that then, this was probably late last decade. I wanted to know of an easier way to get them over to the new PC vs. having to install them one at a time. Some are drag / drop .dll files (easy enough) but many are lengthy install process.

An actual Cakewalk tech responded that I could drag each .dll over to something in the C: drive Windows folder. An .exe or .dll of some kind, located in something like System 32. That installs them quickly. I can't find that post anymore. Can anyone help?

If that is true than its likely he was referring to DX plugins. VSTs need to be in a scan path. 

I wish I could tell you there was an easy way. but in all my years, I have found there is not.
even you drag those DLL's over to your new laptop/desktop, more often than not they need the resource files that accompany them. if not you would load the plug in and be greeted with a nice welcome "failed to load".
Some plug ins however are only DLL and resource files are compressed with the DLL. now which ones are which...your guess is possibly as good as mine.
 
I typically to a clean install (Windows OS / everything) every 8 - 12 months to keep my PC nice and fresh.
I like a clean registry. I used to do system images but I've gotten away from that and just installed everything from scratch. your system will thank you for it as well.

If there is an easy way I sure would like to know about it.  I like easy!

Also by dragging just the dll over you would miss out on the many plugins that can also operate as stand alone programs. Eg most instruments have a stand alone version as do many guitar fx and processors like Ozone etc.