Are you trying to sign in to Messenger, but all you see is error code 80072ee7? Here’s a possible solution for you.

• Click Start, All Programs, Accessories.
• Right-click the entry Command Prompt, and choose Run as administrator from the appearing context menu.
• When Windows asks for your consent, click Continue.
• Type the following line, and press Enter:
  ipconfig /release
• Type the following line, and press Enter:
  ipconfig /renew
• Close the window.
• Retry to sign in to Messenger.

If this does not solve your problem with Messenger error code 80072ee7, please contact http://support.live.com/ for further assistance.

Source: http://messengermaximal.spaces.live.com/Blog/cns!40F43EC9BA81D814!5276.entry