There were alot of people responding to this so I hope you don't mind that I started another thread to record my observations.
First off, I wasn't there. So my response is limited to the content of the thread.
E04 or error messages on the LASER are caused mostly by operator error. It is because that LASER was unable to lock onto the target for some reason. I read that you had yours mounted on a tripod? This limits the operators on the fly adjustment and could be the reason that you get the error message. Remember, we are dealing with a beam of infered light and as we all learned somewhere in our schooling, light cannot bend. It can only be reflected.
Try this next time. Hold the LASER against the cheek of your strong eye. Brace your elbows against a solid object. If I am in my car then I use the steering wheel or the Computer.
Then don't forget to breath.......Remember, this is a highly accurate piece of hardware. We use the survey feature for accident reconstruction.
Another thing I noticed is that the distances were up to 2000 feet. In the real world the distance is more like 200 to 900 feet. It takes a steady hand and a working knowlege of the LASER to have it be accurate outside that range. That too could account for your error messages.
Hope this helps and I look forward to seeing how this effects your results.