Do you have at least 1 bar of 3G or 4G service inside your home/office?
Cel-Fi just needs one bar of 3G or 4G signal to deliver 5 bars!
Try placing a phone call inside your home where you think coverage is best. This would be a place that you would put your Window/Network Unit to receive signal from the cellular tower. While placing the call take a look at the top of your phone, just near the number of bars you should see a network type symbol. What you want to see is either a 3G or 4G logo. It is also important to make sure you can successfully hold calls in this location 100% of the time, anytime of day.
The Cel-Fi system is not compatible with older cellular technologies. Simply put, we will not recognize, pick up, or boost a 2G or EDGE cellular network. Some locations still use this technology because the cellular network provider has not upgraded the network in that area.