Error, "The Temp folder is on a drive that is full..." when installing Acrobat 8 trial or Adobe Reader 8 (Windows Vista)

When you install Adobe Reader 8 on Windows Vista you see the error
message, "The Temp folder is on a drive that is full or is
inaccessible. Free up space on the drive or verify that you have write
permission on the Temp folder."
Reason
You have turned off User Account Control or you are logged in using
the default administrator account.
Solution 1: Enable User Account Control.
   1. In Control Panels, choose User Accounts.
   2. Click "Turn User Account Control on or off".
   3. Check the box to "Use User Account Control (UAC) to help protect
your computer" and then click OK.
   4. Restart your computer.
   5. Install Adobe Reader 8.
      Note: You can turn off User Account Control after you
successfully install Adobe Reader.
Solution 2: Run the installer in XP Compatibility Mode.
   1. Download the Adobe Reader installer from the Adobe website. When
you are prompted to run or save the file, choose save. Save the file
to your desktop.
   2. On the Desktop, right-click the AdbeRdr80_en_US file and
thenchoose Properties.
   3. Click the Compatibility tab.
   4. Under Compatibility Mode, check Run this program in
compatibility mode for: and choose Windows XP (Service Pack 2) from
the drop down list.
   5. Click Apply, then click OK to close the Properties window
   6. Double-click the AdbeRdr80_en_US file and continue with the
installation.