I can’t for the life of me install in Windows 10 any VST plugins in the 3.1.3 version of Audacity.
Once downloaded I get the warnings that I need permission to move the folder around in Windows and if I omit the warning and get the effect into the plugin folder Audacity won’t enable the effect. I hope I explained the problem clearly and any help would be very much appreciated.
Thanks in advance. tony
What plug-in?
Some VST plug-ins just don’t work with Audacity. If it’s a commercial plug-in, they usually they have list of “officially supported” hosts. Sometimes it will work if Audacity isn’t listed but if not “you can’t complain”. 
Free plug-ins are usually hit-or-miss.
And, 32-bit plug-ins only work with 32-bit Audacity and 64-bit only work with 64-bit.
As DVDdoug wrote above,
ensure that the VST plugins are the same “bits” as your Audacity version.
i.e. 64 bit Audacity will only work with 64 bit VSTs, like wise with 32 bit.
Note also that Audacity (32 and 64 bit) only supports (some) VSTs and does not support VSTi at all.