How to find your system email address
The System Email address is used to automatically pull emails that you have with any profiles (people or organizations) into the Interactions for the profile(s). If you include the System Email in the BCC, CC, or To field (it can go in any, but it's probably a good idea to keep it as a BCC so that it isn't visible) for emails being sent to a profile, LibCRM will record that email interaction automatically.
You can find your System Email address from the Admin > Manage System Emails page.
Additionally, the System Email address is visible on all People or Orgnaization profile pages.