I am having trouble accessing my message centre when I am outside of my local calling area. How can I set up my 7135 to dial a (1) before all local calls?

Closest thing I can think of is to set the auto area code to roaming. On a cell phone you don't have to dial one first just the area code.
Phone prefs>Dialing>Auto Area Code>Roaming.
mg

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I understand that in the US you do NOT require a 1 before any 10 digit phone number but in Canada you do. but, your comment about setting up the local area code in roam may work, I'll just need to confirm whether roam affects my cellular package.

I used the roaming option in the phones Auto Area Code area and it works. THX for all your help!