Access sub-domain when root public_html is protected with .htaccess password

Access your site via ftp or cPanel/plesk, making sure that hidden-files are visible.

Find your .htaccess file. Make a backup on the server by copying & renaming (uploading a .htaccess file with the wrong encoding could break it and make things even worse)

Find the lines which start with / look like the following (or thereabouts):

AuthUserFile %variable stuff here%
AuthGroupFile %more variable stuff%
AuthName %variable stuff%
AuthType %variable stuff%
require %variable stuff%

prefix those lines with a bang, hash, pound-sign, or number-symbol (whichever you prefer to call it)

# AuthUserFile %variable stuff here%
# AuthGroupFile %more variable stuff%
# AuthName %variable stuff%
# AuthType %variable stuff%
# require %variable stuff%

If you want, you can look in the file that AuthUserFile points to & change the password to something else.

If you want to remove the password protection from the sub-domain try adding the following to the .htaccess file in the sub-domain directory:

# allows any user to see this directory
Satisfy Any

Please note that the syntax changed in Apache 2.4, this should have the same effect

Require all granted

ref: https://stackoverflow.com/questions/1431378/how-to-remove-htaccess-password-protection-from-a-subdirectory