Serialization of ‘SimpleXMLElement’ is not allowed

Recently on the plugin list screen in the admin we get this error. It does not seem to affect anything else.

Redis is running and it seems to be hitting from the Query Monitor stats.


Error establishing a Redis connection

Serialization of 'SimpleXMLElement' is not allowed

This means that the connection information in your wp-config.php file are incorrect or that the Redis server is unreachable.

  • Are you sure you have the correct Redis host and port?
  • Are you sure Redis server is running?

If you need help, please read the installation instructions.


Status: Connected
Client: Predis (v2.1.2)
Drop-in: Valid
Disabled: No
Ping: PONG
Errors: []
PhpRedis: Not loaded
Relay: Not loaded
Predis: 2.1.2
Credis: Not loaded
PHP Version: 8.0.28
Plugin Version: 2.4.1
Redis Version: 6.0.16
Multisite: No
Metrics: Enabled
Metrics recorded: 73
Filesystem: Content directory is not writable.
Global Prefix: "wp_"
Blog Prefix: "wp_"
WP_REDIS_PLUGIN_PATH: ".../wp-content/plugins/redis-cache"
Global Groups: [
Ignored Groups: [
Unflushable Groups: []
Groups Types: {
    "blog-details": "global",
    "blog-id-cache": "global",
    "blog-lookup": "global",
    "global-posts": "global",
    "networks": "global",
    "rss": "global",
    "sites": "global",
    "site-details": "global",
    "site-lookup": "global",
    "site-options": "global",
    "site-transient": "global",
    "users": "global",
    "useremail": "global",
    "userlogins": "global",
    "usermeta": "global",
    "user_meta": "global",
    "userslugs": "global",
    "redis-cache": "global",
    "counts": "ignored",
    "plugins": "ignored",
    "themes": "ignored",
    "blog_meta": "global",
    "theme_json": "ignored"
Drop-ins: [
    "Query Monitor Database Class (Drop-in) v3.12.3 by John Blackbourn",
    "Redis Object Cache Drop-In v2.4.1 by Till Krüss"


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