Open VZAccess Manager.
From the Windows desktop, click Start > All Programs (Programs) > VZAccess Manager.
With Windows 10, click Start > Apps icon (located in the top-left corner) > All apps (located in the bottom-left corner) > VZAccess Manager.
Click Options > Network Selection.
From the Network Mode field, select the desired option.
If switching to GSM Mode, repeat step 2 then select the desired option from the Network Selection field.
If selecting Automatic, click Close.
If selecting Manual, ensure that the desired network is selected from the Please select a network and press Register field then click Register.
The network with the strongest signal will be used.
A selected network will be used.
The preferred international carrier is automatically selected. You can manually tap an alternate carrier but it may require as many as six registration attempts with that carrier prior to successful registration.
If (or when) presented with a notification screen, click OK.