Plugin Installation Problems

This page covers what to do when the plugin ZIP downloads fine, but WordPress cannot install it. It applies to all SweetCode plugins, including Pixel Manager for WooCommerce, Google Automated Discounts for WooCommerce, and Google Customer Reviews for WooCommerce.

In almost every case we have seen, this is not a problem with the plugin ZIP. It is the server or a firewall in front of it that refuses the upload.

Symptoms

Any of these point to a blocked or aborted upload:

• Plugins → Add New → Upload Plugin spins forever and nothing happens
• The upload ends in a blank page, a white screen, or an HTTP 500 error
• You see Installation failed, The link you followed has expired, or HTTP error
• You see a 403 Forbidden, a 413 error, or the connection is reset mid-upload
• WordPress asks you for FTP credentials to complete the installation

Step 1: Rule out the ZIP and the plugin

1. Re-download the ZIP from your customer account. An interrupted download leaves a truncated archive that no server can install.
2. Open the ZIP locally. It should contain exactly one plugin folder. If your browser or macOS unpacked it automatically, re-zipping the folder yourself often produces a nested structure WordPress rejects, so always upload the original file.
3. Try uploading a different plugin ZIP of a similar size, for example any plugin downloaded from wordpress.org. If that upload fails too, the problem is your server, not our plugin, and the rest of this page applies.

Step 2: Install the plugin via SFTP or FTP

This is the fastest way to get the plugin running. It bypasses the WordPress uploader completely, and with it every server rule that blocks the upload.

1. Unzip the plugin ZIP on your computer. You get a single folder named after the plugin, for example woocommerce-google-adwords-conversion-tracking-tag for the Pixel Manager.
2. Connect to your server with an SFTP or FTP client, or open the file manager in your hosting control panel.
3. If you are replacing an older version of the same plugin, deactivate it in WordPress first, then rename its existing folder in wp-content/plugins/ by appending -old to the folder name. Rename it rather than deleting it through the WordPress Delete button, because the WordPress delete runs the plugin's uninstall routine and can drop its settings.
4. Upload the unzipped folder into wp-content/plugins/.
5. Go to Plugins in WordPress. The plugin now appears in the list. Activate it and enter your license key.
6. Once everything works, remove the renamed old folder.

Your settings and your license are stored in the database, not in the plugin folder, so a manual installation keeps both.

:::tip Do you have SSH access? Then a single command does the same thing: wp plugin install /path/to/plugin.zip --activate :::

If you prefer to skip the ZIP altogether, our plugins can also be installed with Composer. See Install Plugins with Composer.

Step 3: Have your hosting support fix the cause

The manual installation is a workaround. Your site will hit the same wall on the next plugin upload or update, so it is worth getting the underlying server configuration fixed. These are the usual causes:

Cause	What you typically see
upload_max_filesize or post_max_size set too low	The uploader rejects the file immediately, or the error mentions the file exceeding a limit
max_execution_time or memory_limit too low	A long spinner, then a blank page or an HTTP 500
A mod_security or WAF rule on the plugin upload endpoint	A 403 Forbidden, a generic "blocked" page, or a reset connection
A request size limit in a reverse proxy or CDN in front of the site	A 413 error, often after the upload appears to complete
Wrong ownership or permissions on wp-content/plugins/, or a read-only filesystem	WordPress asks for FTP credentials, or reports that it could not create a directory
A full disk or a filled hosting quota	Errors about not being able to copy or write files

Only your host can look into most of these, so open a ticket with them and give them something concrete to work with:

Uploading a plugin ZIP through the WordPress admin (/wp-admin/update.php?action=upload-plugin) fails on my site. Please check the mod_security/WAF log and the PHP error log for the attempt at [date and time, including your time zone], and let me know which rule or limit blocked it. Please also confirm the effective values of upload_max_filesize, post_max_size, max_execution_time, and memory_limit for the site, and raise them if they are below the WordPress recommendations.

Note that our plugin ZIPs are not unusually large. If a small ZIP fails to upload, a firewall rule or a timeout is a far more likely cause than a size limit, so ask your host to check the firewall logs specifically, not just the PHP limits.

Step 4: If it still does not work

Contact us through support or at [email protected], and include:

• Which plugin and which version you are trying to install
• Your hosting provider, and whether the site sits behind a CDN or a security service
• The exact error message or a screenshot of what you see
• Whether a plugin ZIP from wordpress.org fails in the same way
• Your WordPress, WooCommerce, and PHP versions, from Tools → Site Health → Info

Related pages

• License Management for downloads, license keys, and installing the pro version
• Pixel Manager installation
• Google Automated Discounts setup
• Google Customer Reviews setup