Apple – Support – Discussions – Publish Error ….  Turns out that he just needed to follow step #2, delete the iWeb preference file.  Still this is good troubleshooting if that doesn’t fix it.  Thanks Old Toad.

1 – close iWeb.
2 – delete the iWeb preference file, com.apple.iWeb.plist, that resides in your User/Library/Preferences folder.
3 – go to your User/Library/Caches/com.apple.iWeb folder and delete the contents.
4 – reboot.
5 – launch iWeb and see if there’s any improvement.

If that doesn’t help continue:

6 – move the domain file from your User/Library/Application Support/iWeb folder to the Desktop.
7 – launch iWeb, create a new test site and save.
8 – go to the your User/Library/Application Support/iWeb folder and delete the new domain file.
9 - move your original domain file from the Desktop to the iWeb folder.
10 – launch iWeb and try again.