Update Firmware Version 1.2.3 incorporates the following improvements and fixes:

Phenomenon in which the settings of the Speedlite Transmitter ST-E2 revert to the default settings when both the camera and the ST-E2 are set to auto power off.

Macro Ring Lite (MR-14EX, MT-24EX) and slave flashes do not sync while shooting wirelessly.

Firmware
The new firmware (Version 1.2.3) is now available for download by clicking here: 7D Firmware Update 1.2.3

The Version 1.2.3 firmware being released this time is for cameras with firmware up to Version 1.2.2. If the camera’s firmware is already Version 1.2.3, it is not necessary to update the firmware.

Q&A

What’s are the changes in the Version 1.2.3 firmware?
The following fixes have been incorporated.
Fixes a phenomenon in which the settings of the Speedlite Transmitter ST-E2 revert to the default settings when both the camera and the ST-E2 are set to auto power off.
Fixes a phenomenon in which the Macro Ring Lite (MR-14EX, MT24-EX) and slave flashes do not sync while shooting wirelessly.

Are the previous versions of firmware included in version 1.2.3?
Yes, the following improvements from the previous version are included:
(Previous) Version 1.2.2.