Purpose of space x's SXM-7 satellite.
It is a radio communication satellite, which was designed to serve the Sirius subscribers across the U.S, Carribbean and Canada.
Sirius XM holdings inc. is an American broadcasting company, which provides online radio and satellite radio service operating system in U.S. Both XM satellite radio and Sirius satellite radio merged together and formed as Sirius XM radio.
Why the launch was called off ? 
Falcon 9 was planned to launch from space launch complex 40 @ Cape Canaveral space force station in Florida and launch was called off 30 secs prior to lift-off. Launch engineers called a Hold in the countdown. The main reason is the crew want to perform some additional ground systems checkouts.
Falcon 9 was planned to launch from space launch complex 40 @ Cape Canaveral space force station in Florida and launch was called off 30 secs prior to lift-off. Launch engineers called a Hold in the countdown. The main reason is the crew want to perform some additional ground systems checkouts.
Next launch of SXM-7.
Next launch was planned to Dec 13, Sunday, space launch complex 40 @ cape Canaveral space force station, Florida.
What happened in next launch?
SXM-7 was successful made a lift-off and perfectly kept in the orbit. It's boosters made a successful landing burn.
This is the exclusive image of SXM-7's launch.
The rocket boosters used in this falcon 9 was landed perfectly 7th time back to earth and 69th successful first stage booster recovery of space x.
The 7 ton payload was separated and kept in the orbit successfully.
This SXM-7 satellite will serve for more than 15 years for U.S, Canada and Carribbean.