The DEFAULT WiFi SSID/password is located on the side of the gateway...
If having difficulty accessing by default, perform a factory reset of the gateway by depressing and holding the reset button located on back of gateway for 30 seconds.... After about 5 minutes the gateway should be back up, the default settings should work.
For the i38hg the SSID/password is located on the front cover of the iPSU, power supply unit size of a white toaster.
There is no user access to the Wireless Access Point aka WAP (401, 501, 2500) used for Uverse wireless receivers outside using the WPS button on the WAP.
While not familiar with DirecTv wireless router for the wireless genie, I do not believe there is user access, as again only a WAP, not internet access that the Uverse gateway provides. If issue is with DTV router, please ask in the DTV forum.
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No label stuck on the side or bottom or back? Strange? If you can set up an ethernet connection between your computer and your gateway (yellow port) use your computer's browser to access the gateway (192.168.1.254). The status page will show the ssid and password.
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