There are two things that you can try to get rid of this error. The first is to delete the cache file, here are instructions on this:
common_installation_issues.pdf
If you still have the error after doing this there might be a corruption of your configuration folder. If this is the case you will need to rename it, here are the instructions for this:
showpost.php?p=12293&postcount=2
Please post back and let us know if the issue persists after trying this.