Install and activate POM Cache

Installation has two parts: WordPress installs the plugin, while an administrator manually connects WordPress’s early cache bootstrap and Apache delivery. Activating the plugin alone does not complete the cache setup.

This guide assumes the requirements and compatibility review is complete.

1. Protect the current configuration

Before changing the installation:

1. Back up wp-config.php.
2. Back up the main .htaccess.
3. Copy the current wp-content/advanced-cache.php file if one exists.
4. Record which cache plugin or deployment process currently owns that drop-in.
5. Prepare a public staging URL or a low-risk page for the first-cache test.

Do not overwrite another plugin’s drop-in while that cache solution is still active.

2. Install the release package

Use the production ZIP supplied through your POM account. It includes the runtime dependencies required by POM Framework.

On a single-site installation:

1. Open Plugins → Add Plugin.
2. Select Upload Plugin.
3. Upload the POM Cache ZIP and install it.
4. Select Activate Plugin.

On multisite:

1. Open Network Admin → Plugins → Add Plugin.
2. Select Upload Plugin.
3. Upload the POM Cache ZIP and install it.
4. Return to Network Admin → Plugins.
5. Select Network Activate for POM Cache.

The normal deployment directory is:

wp-content/plugins/pom-cache/

If WordPress reports that POM Framework is missing, the package is incomplete. Install the official release ZIP again; do not enable caching with a partial source copy.

3. Add the cache bootstrap constants

Edit wp-config.php and add:

define( 'WP_CACHE', true );
define( 'POM_CACHE_HOME', WP_CONTENT_DIR . '/plugins/pom-cache/' );

Place them before the final WordPress bootstrap, commonly the line that loads wp-settings.php.

Use the actual plugin path if the content or plugin directory is customized. Do not use a public URL. POM_CACHE_HOME is a filesystem path with a trailing slash.

POM Cache reads these values but never writes them.

4. Install the WordPress cache drop-in

Copy:

wp-content/plugins/pom-cache/pom-cache-advanced-cache.php

to:

wp-content/advanced-cache.php

Keep the destination filename exactly advanced-cache.php; WordPress core does not look for a product-specific name.

The plugin does not create, overwrite, update, or delete this file. When a later release changes the source drop-in, deployment must compare and replace the installed copy deliberately.

5. Prepare cache storage

The default base is:

wp-content/cache/

POM Cache creates its HTML files below pom-cache/ and progressive JSON below its separate JSON tree. Confirm that:

• PHP can create directories and files below the base;
• Apache can read the resulting files;
• storage persists for as long as cached responses are expected to remain valid;
• all origin nodes use a consistent storage strategy.

Do not enable caching if the configured base resolves to an unsafe or unintended location.

6. Verify the read-only environment checks

Open:

• Settings → POM Cache → Advanced on a single-site installation;
• Network Admin → Settings → POM Cache → Advanced for the multisite network screen; or
• Settings → POM Cache → Advanced in a subsite administration when a super administrator needs to review that site’s effective settings.

In WordPress configuration, confirm that all three checks show OK:

• Drop-in
• POM_CACHE_HOME
• WP_CACHE

Also confirm that WordPress does not show the Permalink structure error notice. If it does, configure a custom structure under Settings → Permalinks before continuing.

7. Install the Apache rules

In Advanced → Apache rules, copy the displayed rules into the main .htaccess before the standard WordPress rewrite block.

If progressive JSON will be served directly by Apache, review the separate Progressive JSON Apache rules as well. They are optional until that cache is configured.

After saving .htaccess:

1. request a normal public page;
2. request /wp-admin/;
3. confirm both return normally;
4. revert the .htaccess backup immediately if the server returns an error or redirect loop.

The generated rules assume the displayed cache location and standard document-root mapping. Review custom multisite host/path mapping rather than copying blindly.

8. Leave caching disabled until verification

Activation initializes the settings structure, but General → Runtime → Caching should remain Disabled until:

• the environment checks are all correct;
• the Apache rules have been reviewed;
• the license has been validated;
• a suitable anonymous test page has been selected.

Next, activate the POM Cache license, then use Verify your first cached page to enable caching under observation.

Installation result

A complete installation has:

• POM Cache active, or network-active on multisite;
• its production dependencies present;
• WP_CACHE enabled;
• POM_CACHE_HOME pointing to the installed plugin;
• the expected POM Cache drop-in at wp-content/advanced-cache.php;
• writable cache storage;
• reviewed Apache rules;
• no active cache generation until the first-cache test.

If any Advanced status remains Needs manual change, resolve that item instead of using Fix Configuration as a substitute. That button cannot edit the files involved.