That's OK but there could be a different reply depending on the versions now as things have changed over the past several versions.
Try copying the php5ts.dll and php_mysql.dll found in the \xampp\php folder to the \xampp\apache\bin folder then try and restart Apache and MySQL.
This has worked for some who had this issue.
The error can be caused by several things so it will be trial and error.
These search results
may help save you some time.