Windows Server 2012 Essentials may occassionally report that it's Open Manage logs are full.  These can be cleared by:

• Log onto rthe server console as an administrator
• Click on "Programs" and then follows "Dell OpenManage Applications|Server Administrator|Server Administrator"
• Log onto the system using an administrative account on the domain
• Click on the "Logs" tab
• Go through the Hardware, Alert and Command sections and click on "Clear Log"