1. Press and hold the Reset button on the back for 12 seconds, until the green and orange lights go off.
2. Disconnect your phone from all known networks, and then connect to the SSID broadcast by the DataLogger, password is 123456789
3. Browse to http://10.10.100.254
4. Login using the following credentials:
Username: admin
Password: 123456789
5. Click the 'Quik Set' menu option from the left hand side and input the SSID and Password for the network you want the Datalogger to connect to.
6. If successful, the green WiFi light on the Datalogger should turn solid green.
All the above is also explained in the following video: https://www.youtube.com/watch?v=6KlpJMFPu60