I want to listen to messages left on my cell phone voicemail from a landline phone
Checking your voicemail from a landline phone:
1. Make sure your cell phone is set up to allow voicemail to be checked from a landline phone. If your cell phone requires a special feature to be enabled, follow the steps in your instruction manual to ensure you can check the voicemail from another phone.
2. Call your cell phone from a landline phone. The landline phone you use must be a touch-tone phone, or you won't be able to enter the required PIN or password.
3. When your cell phone's voicemail picks up and the answering message starts to play, press the star key (*) on your landline phone immediately. This will trigger an automated recording that will ask you to input your password or PIN.
4. Use the keypad on your landline phone to input the password or PIN you use to check your voicemail from your cell phone. When you've finished entering the information, press the pound (#) key.
5. Listen to the instructions relayed by the automated message. They will tell you how many voicemail messages you have and give you options for checking them, deleting them, saving them or storing them as new messages. Every phone is slightly different, so listen carefully to the options. source