If the password is set, the plug-in cannot connect

Can you post your diagnostics please? Are you seeing any error in your logs?

When the requirepass key is not set in the redis.conf file, the plug-in is connected. The diagnostics is :

Status: Connected
Redis Version: 5.0.7
Client: PhpRedis (v5.1.1)
Drop-in: Valid
Ping: 1
Redis Extension: 5.1.1
Predis Client: 1.1.1
PHP Version: 7.3.6
Multisite: No
Global Prefix: "wp_"
Blog Prefix: "wp_"
WP_REDIS_DATABASE: 1
WP_REDIS_PASSWORD: "**************************************"
Global Groups: [
    "blog-details",
    "blog-id-cache",
    "blog-lookup",
    "global-posts",
    "networks",
    "rss",
    "sites",
    "site-details",
    "site-lookup",
    "site-options",
    "site-transient",
    "users",
    "useremail",
    "userlogins",
    "usermeta",
    "user_meta",
    "userslugs",
    "blog_meta",
    "wpjam_list_cache",
    "wpjam_messages"
]
Ignored Groups: [
    "counts",
    "plugins",
    "themes"
]
Unflushable Groups: []
Dropins: 
 - Query Monitor Database Class v by 
 - Redis Object Cache Drop-In v1.5.5 by Till Krüss
Plugins: 
 - Elementor v2.8.2 by Elementor.com (Active)
 - Elementor Pro v2.8.2 by Elementor.com (Active)
 - Lumise - Product Designer Tool v1.7.6 by King-Theme (Active)
 - Mailchimp for WooCommerce v2.3 by Mailchimp (Active)
 - Query Monitor v3.5.2 by John Blackbourn (Active)
 - Redis Object Cache v1.5.5 by Till Krüss (Active)
 - Shortcode in Menus v3.5 by Gagan Deep Singh (Inactive)
 - Wechat Social v1.2.9 by 迅虎网络 (Active)
 - WooCommerce v3.8.1 by Automattic (Active)
 - WooCommerce Admin v0.23.2 by WooCommerce (Inactive)
 - WooCommerce Chinesize by Wenprise v1.0.2 by WordPress智库 (Inactive)
 - WooCommerce微信支付(红包) v2.2.4 by 迅虎网络 (Active)
 - Wordfence Security v7.4.2 by Wordfence (Inactive)
 - WordPress Importer v0.6.4 by wordpressdotorg (Active)
 - WPJAM BASIC v3.9 by Denis (Active)

When the requirepass key is set in the redis.conf file, the plug-in is not connected. The diagnostics is：

Status: Not Connected
Redis Version: Unknown
Client: PhpRedis (v5.1.1)
Drop-in: Valid
Ping: 1
Redis Extension: 5.1.1
Predis Client: 1.1.1
PHP Version: 7.3.6
Multisite: No
Global Prefix: "wp_"
Blog Prefix: "wp_"
WP_REDIS_DATABASE: 1
WP_REDIS_PASSWORD: "**************************************"
Global Groups: [
    "blog-details",
    "blog-id-cache",
    "blog-lookup",
    "global-posts",
    "networks",
    "rss",
    "sites",
    "site-details",
    "site-lookup",
    "site-options",
    "site-transient",
    "users",
    "useremail",
    "userlogins",
    "usermeta",
    "user_meta",
    "userslugs"
]
Ignored Groups: [
    "counts",
    "plugins",
    "blog-details",
    "blog-id-cache",
    "blog-lookup",
    "global-posts",
    "networks",
    "rss",
    "sites",
    "site-details",
    "site-lookup",
    "site-options",
    "site-transient",
    "users",
    "useremail",
    "userlogins",
    "usermeta",
    "user_meta",
    "userslugs",
    "blog_meta",
    "wpjam_list_cache",
    "wpjam_messages",
    "themes"
]
Unflushable Groups: []
Dropins: 
 - Query Monitor Database Class v by 
 - Redis Object Cache Drop-In v1.5.5 by Till Krüss
Plugins: 
 - Elementor v2.8.2 by Elementor.com (Active)
 - Elementor Pro v2.8.2 by Elementor.com (Active)
 - Lumise - Product Designer Tool v1.7.6 by King-Theme (Active)
 - Mailchimp for WooCommerce v2.3 by Mailchimp (Active)
 - Query Monitor v3.5.2 by John Blackbourn (Active)
 - Redis Object Cache v1.5.5 by Till Krüss (Active)
 - Shortcode in Menus v3.5 by Gagan Deep Singh (Inactive)
 - Wechat Social v1.2.9 by 迅虎网络 (Active)
 - WooCommerce v3.8.1 by Automattic (Active)
 - WooCommerce Admin v0.23.2 by WooCommerce (Inactive)
 - WooCommerce Chinesize by Wenprise v1.0.2 by WordPress智库 (Inactive)
 - WooCommerce微信支付(红包) v2.2.4 by 迅虎网络 (Active)
 - Wordfence Security v7.4.2 by Wordfence (Inactive)
 - WordPress Importer v0.6.4 by wordpressdotorg (Active)
 - WPJAM BASIC v3.9 by Denis (Active)

By the way, my password is 38 characters.

php_error_log :

[27-Dec-2019 02:10:06 UTC] RedisException: NOAUTH Authentication required. in /opt/lampp/htdocs/wp-content/object-cache.php:572

Try moving the password all the way to the top of your config file.

Thanks for your reply. I did, but the problem is still there.

Can you try defining the host and port explicitly?

In wp-config.php, set as follows

define( 'WP_REDIS_HOST', '127.0.0.1' ); 
define( 'WP_REDIS_PORT', '6379' ); 
define( 'WP_REDIS_DATABASE', 1 );   
define( 'WP_REDIS_PASSWORD', 'mypassword_mypassword_mypassword_mypas' ); 

Still unable to connect

That’s very strange, since it’s working for everyone else.

Are you doing something fancy, or have you modified the plugin in any way?

https://serverfault.com/questions/722803/redis-error-noauth-authentication-required

Thanks for your help, I will try not to use remote access redis

Did you solve it? I have the same issue