Guys,
I spoke with Castle support yesterday and relayed my problem. We have found the problem. Seems that some laptop or tablets don't have enough power in the USB connection to allow the ESC to update. As I indicated in my first post my personnel laptop computer (Sony Vaio) had a tune-up and update by my local Geek Squad. I the process my Castle Link got wiped. This machine runs Windows 7 and to load Castle Link you need to be in Administer mode (as William said).
I was rushing to get out to the Palmetto, FL contest last Friday and figured I could just use my MS Surface Pro tablet (it runs Windows 8.1) which I had Castle Link 3.56.17 loaded onto. All I needed to do was lower the rpm, simple. When I tried to load the new rpm update it wouldn't complete the update. I tried several things - tried to load a newer firmware - still nothing. When I went to test run the system (which had worked fine before I started trying to change the rpm) the controller would just sit there, no beep, no spin-up. I thought I toasted it. In the last ditch effort I call Castle and they said try the other computer. Well I loaded CLink in admin mode and then connected the ESC same as I had been and Ta-Da - new firmware and settings when in just fine.
I really would like to see if there is a way to get more power out to the USB port on the Surface but I think the problem is the battery is either too low voltage or doesn't have enough current available for our needs.
Best, DennisT