problem installing dynamic compressor

Not having any success installing dynamic compressor
Windows 7 Home Premium v6.1 Build 7601:SP1 - latest upgrades installed
Audacity 2.2.2
Have put compress.ny in audacity\plugins folder and also tried in user\app data\roaming\ audacity \plugins but nothing happens
If I click open on it get msg not recognised by audacity
Have also tried similar with but no joy there either.
with the zip get access denied msg
Any suggestions appreciated

Have to enable plugins, (and press OK), before they appear in the effects menu …

Thanks Trebor
That was easy, just a matter of knowing which buttons to press