[TYPO3-install] Existing Website transfer to localhost Version 4.7

[William F]

Hello,

I am trying to install an existing website locally (version 4.7) but the following error comes when I connect:  

#1301648945: Database Error: The current username, password or host was not accepted when the connection to the database was attempted to be established! (More information)

t3lib_error_http_ServiceUnavailableException thrown in file
C:\Users\William\Desktop\Axon Active\XAMPP\htdocs\webseite\typo3\sysext\cms\tslib\class.tslib_fe.php in line 366.

How and where can I fix this database issue?  Please pardon my Typo3 ignorance...

Thank you!