I'm trying to dial an Irish cell phone number from the US. I have the
number in the format 086-xxx-xxxx, and I am attempting to dial
011-353-86-xxx-xxxx, but am getting "call could not be completed as
dialed" when I call from my Verizon cell phone and "the number is
busy" when I call via a calling card. What am I doing wrong?

Ireland has three mobile phone networks. The 86 prefix is used by
Digiphone. 85 is the Meteor system. And 87 is Vodaphone. Is it
possible that the number you are dialing belongs to one of these other
networks, and that you should be dialing 85 or 87 rather than 86? This
is the only possibility I can come up with. You are dialing correctly,
so one might assume--as I am--that the number belongs to one of the
other two networks.

Also, your Verizon cell phone may not be authorized to call outside
North America.  I know I've encountered that when traveling overseas.

When I travel, I am set up to call FROM IRELAND back to the States,
but I've never set up my account to call TO IRELAND.  There's simply
no need when there are much cheaper alternatives.  When I land in
Shannon though, I want to be sure to call home right away.

The other thing is that you may not actually need the 011.  Most
phones are set up with a "+" key.  I know that when I'm calling home
(the US), I use that button (tap twice quickly) and then just dial the
international number.

I'm not an official "Google Answers" person, but I thought this would help you.