Can't see red letters when registering.

I am trying to upgrade my Comcast modem from a Motorola to  an Arris Interactive, L.L.C. tg862g wireless modem supplied by Comcast.

Once the cables are connected, the Internet connects to the Comcast registration screen. On this screen I can enter my account and telephone numbers but cannot see the red verifcation letters.

I have tried on Windows and Linux, and with Firefox, IE, and Chomium. I've cleared the cache and turned off popup blockers and still cannot see the letters. On some browsers I see an icon, on others there is nothing where the verification letters should appear.

What must I do to get the letters to appear?

While here, I guess I ought to mention that the telephone line blinks during initial power up but then extinguishes. I have no phone service with the new modem. Will the telephone start working once the Arris modem is activated?

Thanks.