If you are having problems with uploading firmware or communicating with the gimbal software (RCTimer - Gimbal controller board for example) then most likely the following info will help you.
See communication problem below in Arduino:
Follow this link for instructions:
Remember to update both the "serial port driver" and the "USB serial converter" driver. You will have to update driver, select the browse button and then pick the driver (have disk option), else windows will always take the latest driver available.
Trust you will find this useful as I did.