SharePoint 2013 Errors

1. When you try to create a site collection using Publishing Portal template, you get the following error:
   
   “The group name is empty, or you are using one or more of the following invalid characters: " / \ [ ] : | < > + = ; , ? * ' @”
   
   I am still working on resolving this error.
   
2. Central Admiration health analyzer icon on the main page is not displayed correctly
   It looks like a JavaScript issue but still there is no information available on why it happens and how to resolve it.
   
   
   
3. When uninstalling SharePoint Server 2013, you are asked to provide the product key
   I am not sure why the product key is needed for uninstallation.
   
4. When uninstalling SharePoint Server 2013, the following error is displayed
   
   “Setup cannot continue because a required file is either corrupted or not available. Run setup again from the original source disc or download location”
   
   
   
   I started the setup from the SharePoint 2013 ISO and had to install it on top of the current installation. After completing the setup, I was able to uninstall SharePoint Server 2013