If you downloaded Hoster 3.318 before December 29, 2007 @ 10:30PM, you have a bad installation version.
For some of you, it will install as if everything is OK, removing your prior version, and then when you try to run it you will see the infamous "Serial Number Mismatch..." error message. You can't run this version. You can remove it and re-install your prior version, if you have the prior download installation file.
We have replaced the bad installation version with one that works correctly. This bug has been present for years, but changes in our web script just showed it up with 3.318.
If you downloaded before the above time, please go to your download link and get the new version.
You must have purchased Hoster 3.310 or higher, or an upgrade since May 30, 2006 to install 3.318 for free. Those who haven't will need to buy the Hoster Upgrade (or the Lite Upgrade if that is your version). You can find these links at
http://www.mtu.com/upgrades/hoster.htm.