two XAMPPs are installed in a computer

[dotKer]

I installed "xampp-windows-x64-7.4.11-0-VC15-installer" some months ago at D:/xampp201126.
And I installed "xampp-windows-x64-8.0.0-2-VS16-installer" today at D:/xampp210105.

After I activate Apache and MySQL by clicking the buttons of Apache and MySQL on control panel at D:/xampp201126/index.php, I can open the file D:/xampp201126 by typing "http://localhost/" and I can approach to the phpmyadmin of D:/xampp201126 by typing "http://localhost/phpmyadmin/'.

After I activate Apache and MySQL by clicking the buttons of Apache and MySQL on control panel at D:/xampp210105/index.php, I can open the file D:/xampp210105 by typing "http://localhost/".
And I could approach to the phpmyadmin of D:/xampp210105 just one time by typing "http://localhost/phpmyadmin/'.
I set password "***********" at the phpmyadmin.
After I set the password, I cannot approach to phpmyadmin again any more.

If I try to approach to the phpmyadmin of D:/xampp210105 by typing "http://localhost/phpmyadmin/", it says like the following.

mysqli::real_connect(): (HY000/1045): Access denied for user 'root'@'localhost' (using password: NO)

The phpmyadmin password of D:/xampp210105 is same as the phpmyadmin password of D:/xampp201126 at the moment.
I did, in fact, installed XAMPP at D:/xampp210105 several times today.
At first the The phpmyadmin password of D:/xampp210105 was NOT same as the phpmyadmin password of D:/xampp201126. but now they are same as "***********".

Can I approach to phpmyadmin of D:/xampp210105 by your help?

[Altrea]

And I could approach to the phpmyadmin of D:/xampp210105 just one time by typing "http://localhost/phpmyadmin/'.
I set password "***********" at the phpmyadmin.
After I set the password, I cannot approach to phpmyadmin again any more.

If I try to approach to the phpmyadmin of D:/xampp210105 by typing "http://localhost/phpmyadmin/", it says like the following.

mysqli::real_connect(): (HY000/1045): Access denied for user 'root'@'localhost' (using password: NO)

You need to tell phpmyadmin too that the password has changed.
That can be done in the phpmyadmin config.inc.php

[Nobbie]

If you set a password to phpmyadmin, you have to apply that password as well to the config.inc.php file (which is part of each phpmyadmin installation). Edit the corresponding config.inc.php and watch out for these lines:

$cfg['Servers'][$i]['user'] = 'root';
$cfg['Servers'][$i]['password'] = '';

Apply your password in the password line (see above) and try again.

If you are tired to adapt config.inc.php every time you change your root password, you can instead change the auth_type in your configuration, which is "config" per default. Watch out for that line:

$cfg['Servers'][$i]['auth_type'] = 'config';

Edit that line and change "config" to "cookie":

$cfg['Servers'][$i]['auth_type'] = 'cookie';

In that case, the values of "user" and "password" do NOT MATTER any more (they are ignored by phpmyadmin), instead you will get a login dialog on start of phpmyadmin, apply the credentials of your installation there.