When you use Workspace ES 188.8.131.52 in Internet Explorer 6 or 7 and you log in, open an XFA form, and log out repeatedly, the memory usage increases. Usage increases between 500 KB to 3 MB when you close forms, and up to 30 MB when you log out of Workspace.
This is a bug in Workspace 184.108.40.206. Contact Enterprise Support to obtain a patch for LiveCycle ES 220.127.116.11. Or, use LiveCycle ES 18.104.22.168 or later.