The AT&T Beam 340U modem requires some minor configuration in order to work with the Solo. The necessary software is located here: https://drive.google.com/open?id=0B4jSFInIWcU5Vm4tRDhhRVpjemc
Step 1. Install the AT&T AllAccess app on your computer (has to be Windows based and should automatically install once the modem connects to it).
Step 2. Update the firmware of the modem to the latest version (using the AllAccess app).
Step 3. While AllAccess is running:
- verify the new firmware (go to settings-->about)
- run AC340U_ip_pass_thru_enable file (included in the Google Drive link, not you may need to use Window's "Run As Administrator" if you right-click on the exe file)
Step 4. Close the AllAccess app and run AC430U_autoconnect_disable (included in the Google Drive link, similar to above, it seems to help to "Run As Administrator")
Lastly, place the modem in the unit and verify connectivity.