We have Tab A's that connect to a Sierra Wireless router installed on vehicles. Each tablet connects to a Sierra Wireless router's hidden SSID. We set a static IP for the WiFi connection. We also set the Gateway, Network Prefix Length and DNS1. On Monday we successfully connected each table to it's WiFi network and were able to login to our application. However, today on multiple vehicles (about 5% of them) we received "Authentication Errors" when the tablets were trying to connect to the WiFi network. I went into the Advanced Settings and noticed that the DNS1 was showing as 184.108.40.206. Nothing was changed in the tablet settings as we have the devices locked down using a free App called MobiLock. Also, the problem could be resolved by simply turning WiFi off and then back on. However, this is not a solution that can be utilized moving forward as the operators will not have access to the WiFi settings. Any thoughts on how/why this Authentication Error is occurring?