Error updating firmware Alexmos 3 axis brushless gimbal controller

I am try to updating Firmware on “Alexmos 3 axis brushless gimbal controller” using GUI software Version 2.40b7 and 2.40b6 and getting error message “failed to upload:error writting firmaware:[1] avrdude:stk500_getsync():not in sync: resp=0x00”

Does any body knows what is that mean???

Where did you order your board from? Is it an official version of the alexmos gimbal controler? Usually the error is related to a missing bootloader:

avrdude:stk500_getsync():not in sync: resp=0x00"

So by the sounds of it either you are not using an official board (so you cant update the firmware) or your bootloader as become corrupt for some reason.

Otherwise the other issue could be you are not selecting the correct COM port, or you dont have the correct drivers installed.

I bought at hobby king.com “Quanum AlexMos Brushless Gimbal Controller 3-Axis Kit Basecam (SimpleBGC)”
i download this drivers “CP210x USB to UART Bridge VCP Drivers” Download for Windows XP/Server 2003/Vista/7/8/8.1 (v6.7)
when I try to connect on GUI Software keep said"connecting to COM3…but looks like never connect …
Any idea how to fix this?

There is any tips to help me do firmware update?

Unfortunately not, its possible that the board itself is damaged, or its not an official basecam board in which case the firmware update will not work (as you will need the official basecam bootloader). My suggestion is to contact hobbyking to try get some help from them, or return the alexmos board back if its no longer working.