maybe setupx.dll is corrupt. find it, rename it, and replace it, directions below from various mskb articles.
mskb article ------
In the Search for files or folders named box, type setupx.dll, click Local Hard Drives in the Look in box, and then press ENTER.
Right-click the Setupx.dll file, click Rename, type setupx.old, and then press ENTER.
Extract a new copy of the Setupx.dll file to your computer.
mskb article ------
You can extract files directly to the destination folder when you start your computer with the Startup disk.
The default source folder for Microsoft Windows installation files is the C:\Windows\Options\Install folder.
If you need to make a Startup disk to run Extract, use the following steps:
Click Start, point to Settings, and then click Control Panel.
In Control Panel, double-click Add/Remove Programs.
On the Startup Disk tab, click Create Disk.
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The general form of the extract command is:
extract source path\ file /L c:\windows\command
For example, if the source path is C:\Cabs, the extract command is
a:\extract drive:\cabs\file /L drive:\windows\path
where drive is the drive on which Windows is installed (typically drive C), path is the destination folder for the extracted file, and file is the file you want to extract.
Type the following command at the command prompt, making the appropriate substitutions as previously noted, and then press ENTER:
a:\extract source path\ file /L c:\windows\command