BBB will boot upgraded Debian from SD, but won't flash

I’ve been trying to upgrade the OS on my BBB for a week, but I always get the same result. The BBB will boot from the SD (verified with uname), but will not flash the eMMC. If I remove the SD and reboot I’m back to the original image. The image is

bone-debian-7.8-lxde-4gb-armhf-2015-03-01-4gb.img.

Am I misunderstanding something?

The SD card was created using dd on a mac.

Regards,
John

I’ve been trying to upgrade the OS on my BBB for a week, but I always get the same result. The BBB will boot from the SD (verified with uname), but will not flash the eMMC. If I remove the SD and reboot I’m back to the original image. The image is

bone-debian-7.8-lxde-4gb-armhf-2015-03-01-4gb.img.

Am I misunderstanding something?

There a separate image for flashing
Follow this to convert your current image.

http://elinux.org/Beagleboard:BeagleBoneBlack_Debian#Flashing_eMMC

Ahhhhhh that was the problem. Works great now. Thanks.