Can't update A7R Firmware

[ACH DIGITAL]

I just bought a mint condition A7R on Ebay. Everything works fantastic.
The actual firmware is the 1.02. I downloaded the Update_ILCE7RV110 from the official Sony Us site.
I'm trying to do the update from a Mac with a fully charged Sony original battery and fallowing the exact steps as described.
When I get to connecting the camera to the computer it stays long on verifying connection, then it tells to turn off the camera, pull the battery and restart the update software.
The camera is on Mass storage USB mode.
It happens again and again. I tried in my macbook pro and is the same. Changed USB cable and is the same.
Curious is that I get connection to other software like Capture One with no problem.
Any Ideas??

[ACH DIGITAL]

Found the problem:
Mac OS X 10.10 Driver Loader
What Does This Do?
This utility installs the necessary application needed for software updates if you are running Mac® OS X 10.10.
Applicable Products and Operating Systems (see full list...)
Model:ILCE-7ROperating System:
Mac OS® X

[E.J. Peiker]

I've had all sorts of trouble doing any Sony firmware update on a Yosemite based Mac.  I just use an old PC laying around specifically for that as it's quick and seamless.  Sony has the most convoluted firmware update process of any camera manufacturer.

[ACH DIGITAL]

I've had all sorts of trouble doing any Sony firmware update on a Yosemite based Mac.  I just use an old PC laying around specifically for that as it's quick and seamless.  Sony has the most convoluted firmware update process of any camera manufacturer.

Yeah it is a good idea to have a windows machine around for some works. I hate windows though. A friend of mine has a Surface with win 8 and I can't even get to the applications panel. My last windows was a XP machine..

[ACH DIGITAL]

I just download a windows version firmware update and it works perfect

After I installed the patch in my mac, it worked perfect. Recomend to follow those instructions and retry.
Thank You