Have installed the pro version and configured and verified domain. on plugins page, encountered the following alert: "Pro version installed, but not active. Did you verify ownership of your domain?" in the settings section clicked the "setup test tool" -> auto configured. problem solved, and then reappeared a day later.
Hmmm... did you make any changes to your WordPress installation in that time by chance? Like install a whole new version of WordPress or anything? The license check system is cached inside WordPress, so it's going to rely on WordPress's cache which could potentially get flushed if you are replacing the caching system with something else or something along those lines. The only other thing I can think of is maybe there was a network connectivity issue between your server and our servers whenever it did the check. If that was the case, the system should automatically sort itself out since it rechecks once in awhile. If it happens again, let me know and I'll see if we can dig deeper into what's going on exactly in your case.
Great Thanks, I've disabled "W3 Total Cache" and the verification error has gone away. What path should i exclude in the cache settings in order to re activate the cache plugin?
I would assume that W3 Total Cache wouldn't be prematurely expiring active cache items. If that's the case you might want to bring it up with their developers, because that is most likely going to be a bug. Better Analytics just uses the standard transients system built into WordPress for it's cache.