What's the proper syntax for nsscon? I'm trying to temporarily disable compression to see if it helps my backups, but nss commands are giving me errors. I'm typing nsscon at the console, then I'm typing nss /EnableFileCompression=Off, but I'm getting this error:

Option "/EnableFileCompression=Off" is unknown for the current NSS configuration and may require other NSS modules to be loaded.

nss /status works.