Yes 4G AppleUSBCDCECMData error/issue Mac OS X
If you are using a recent Apple with a default install of Mac OS X version 10.6.6 or higher, and have problems getting OS X to detect your Yes 4G Go USB dongle despite plugging/unplugging your dongle 5000 times – this may be of some use.
1) Open Terminal
2) Remove your USB dongle
3) Insert your USB dongle
4) In Terminal, type “sudo dmesg” (enter your password when asked)
5) Try to spot this in the jumbled mess of text
AppleUSBCDCECMData: start – Find CDC driver for ECM data interface failed
If you see this, fear not, you just need a newer version of the Yes 4G connect drivers for OS X 10.6.6 and above – you can grab them here.
Note: This “fix” is only for OS X devices that install from a 10.6.6 DVD by DEFAULT. In general, this would mean early 2011 (or later) Macbook Air/Pro. Installing this updated driver probably won’t kill your machine if you are using an earlier version of OS X, but it probably won’t fix your problem either. I hold no responsibility for your OS X device going up in flames and/or growing a pair of legs and running off into the sunset.
UPDATE: The latest drivers from the YTL site “should” work fine. There is no reason to use the drivers listed on this page anymore (unless you like using outdated drivers).