What have you installed, and from what download location or mechanism?
Microsoft Antispyware can be uninstalled via add or remove programs in
control panel in most cases, but there are a few in which the program
appears installed, but the uninstall is not present in add or remove
programs. What is your situation? Do you have icons for Microsoft
Antispyware? Or are we discussing something that was obtained from
WindowsUpdate or AutoUpdate?