When a new version of ARES Commander is available, you should be notified in ARES Commander automatically, if the computer has an internet connection available.
In the lower left side of the ARES Commander desktop a balloon comes up and informs you that an update is available. This update notification feature is available in version 11.8.1058 or higher.

If you use a proxy server in your company then you have to check our homepage for newer versions here (as internet communication may be blocked), and compare the version build number e.g. (Build No. 11.2.211 - Shown in the dialog of _ABOUT command).

Note: Since version ARES Commander 2015 you can control this feature via the OPTIONS dialog under "System Options-->General-->Show notification balloon on updates".