Windows Update is Not Enabled
Before proceeding, you must enable Windows Update. Windows Server AppFabric cannot be installed if Windows Update is not enabled.
To enable Windows Update
Click Start, point to All Programs, and then click Windows Update.
Click Change settings.
In the Important updates section, select a mode of update that enables Windows Update (any selection other than Never Check for Updates), and then click OK.
Click Start, and then click Run. In the Run line, enter Services.msc, and then click OK.
Move to the Windows Update service and ensure that the status for the service is Started. If not, right-click the service, click Start, and then close the Service dialog box.