How do you access voicemail on a Verizon cell phone?

[Deusexmachina]

I have a Verizon phone, and I have been trying in vain to access the voicemail on it. Although I know how to get to voicemail under the "messaging" tab on the menu, when I try to open it, it asks me to enter a password. I never set up any sort of password, nor was I told when when I bought the phone. Does anyone know how to figure out the password for voicemail, or change it?

Also, does anyone know how to change the outgoing message?