We're using Windows Deployment Services (the successor to RIS) on our network. When I originally created the images of the PC's I built-in the username and password using SysPrep. The need arose recently to change the password.

So, without re-creating all the images (we have about 7), is there away to extract the file that contains the password entries from the .WIM file, change it and put back into the .WIM file?

Thanks/...

Yes,
you can mount the images so you can edit the sysprep.inf file.
Install WAIK if not done already.

Open dos box via the Windows PE Tools Command Prompt shortcut.
Then in the box:
1) Prepare:
copype.cmd x86 c:\tempIMG

2) mount:
imagex /mountrw %1 1 c:\tempIMG
where %1 is the path to the image you want to change

3) edit the sysprep.inf in c:\tempIMG\sysprep

4) unmount :
imagex /unmount /commit c:\tempIMG