it is suggested to perform the initial backup via Ethernet for the fastest performance when using a Time capsule. However my MacPro doesn't have an ethernet post??? Am I not understanding the instructions???

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All MacBooks Pro except the MacBook Pro with Retina display have an Ethernet port. See "Connections and Expansions" > http://www.apple.com/macbook-pro/specs/

Note that there isn't an enormous difference between Ethernet and Wi-Fi, even if Ethernet makes the backup a bit faster. If your MacBook hasn't got any Ethernet port, use Wi-Fi

If your MacBook Pro does not have an Ethernet port, then it almost certainly has a Thunderbolt port. You could use a Thunderbolt to Ethernet adapter if you want to use a wired connection for the first backup.

Thunderbolt to Gigabit Ethernet Adapter - Apple Store (U.S.)

Getting a backup done is important....no doubt about that.

But, the Ethernet / Thunderbolt connection will allow that backup to take place 4-5 times faster than using wireless.

initiated backup then cancelled half way and now each time I try to use Time Machine cannot find disk. May try resetting TC

Probably no need to reset the TC....but you may need to erase the TC drive and start over again with a new backup. Post back if you need help with this.