Product review (1 stars): This is a piece of junk with the worst customer support on the planet
This is a piece of junk with the worst customer support on the planet.  This is also the 2nd one I had that was defective.  1st one powered up but would not register so I attempted to do a factory reset, unplugged, held in button, plugged in, no light, nothing, deader than a door knob.  So on to  my second one.  That gateway registered just fine to my 'previously created' account.  Next step, register the sensor.  No go.  Tried more times than I want to remember.  1st tried their on-line troubleshooting which was nothing more than 'factory reset'..  I LOVE this comment...

Batteries are usually the problem.  Make sure they are new and measure 1.42 volts or higher on a digital volt meter.  HA!  Fortunately I HAVE a dvm but tried several brand new batteries.

Next to perform a factory reset on the sensor.  That never worked, never able to get the 18 88 display, ever, then it just sat there with three red blinks.

Now on to their tech support.  Sent email, because their web site says it's faster than calling.  Really?  Ok, sent email, took TWO DAYS for a response from my VERY detailed description of my problem.  I have been in computer repair for over 30 years, I KNOW what to say but they ignored it all.  They reset my account (which was not a problem from what I could tell, the gateway was registered just fine).  and told me (actually pasted the web links in the email) how to reset the gateway.  I responded with a repeat of my symptoms and troubleshooting to date.  They replied another day or so later  with this

First, unplug the gateway for a good 10 minutes.  When you plug it back in, count the blink sets carefully.  If you were working, you should not have 3 blinks...  http://support.lacrossealertsmobile.com/3-blinks.html
Then you should be able to get 18.88 on the sensor by holding firmly long enough.  If it is counting though, you can likewise just take the batteries out for 10 minutes, as well.

That link is for three blinks on the gateway (which is a dns issue, which if I had that, I'd never be able to register it). I don't have three blinks on the gateway, it's on the sensor, so they didn't read my email again!  I replied with another email and have yet to get a response, but decided to give up on this unit and the project it was intended for all together and have sent it back.

Congrats to all who gets one that works, I feel sorry for you when the batteries drop below 1.42 volts and everything goes to lunch and you have to recreate everything to get it back working, if it even does!