Description
There is one string in includes/import_functions.php which works only with UTF-8. If string is in a different format system throws Database error: Invalid SQL.
 
Solution
http://www.viart.com/downloads/import_functions-4.2.zip
 
Download the file above and extract 'import_functions.php' in /includes folder replacing the existing file. Please do not forget to make a backup copy of the current file in case something goes wrong.