---
title: Fixing Download Failures Caused by Server Errors
description: "WordPress plugin download failing with a server error, open_basedir warning or empty ZIP? Server-side causes and fixes."
url: "https://wpfactory.com/docs/fix-download-server-errors/"
updated: "2026-09-27"
category: Troubleshooting
tags:
  - Download Plugins and Themes from Dashboard
---

# Fixing Download Failures Caused by Server Errors

If a download from Download Plugins and Themes in ZIP from Dashboard fails with a server error or an empty ZIP, check for the admin notice about RecursiveIteratorIterator or zlib. Then go to WPFactory > Download plugins and Themes > Advanced Settings, switch the ZIP library, and set a writable temporary directory.

### 1. Check the plugin's system requirements notice

To build a ZIP, Download Plugins and Themes needs the `RecursiveIteratorIterator` class and the `zlib` extension (the `gzopen` function). It checks for both when you start a download and shows an admin notice if either is missing. If you see that notice, ask your host to enable the missing component. The plugin uses `ZipArchive` when it is available and falls back to `PclZip`, so a missing `ZipArchive` extension alone will not stop it, but `zlib` is required in either case.

### 2. Switch the ZIP library

Some server setups produce broken or empty archives with one library but not the other. Go to **WPFactory > Download plugins and Themes > Advanced Settings** and change **ZIP library** (option `alg_download_plugins_dashboard_zip_library`) from ZipArchive to **PclZip**, or the reverse, then retry.

### 3. Set a writable temporary directory

The ZIP is assembled in a temporary directory before it is sent to your browser. If that directory is not writable, the archive can come out empty or the build can fail. In **Advanced Settings**, set **Temporary directory** (option `alg_download_plugins_dashboard_temp_dir`) to a path you know the web server can write to, then try again.

### 4. Resolve open_basedir restrictions

An `open_basedir` restriction can block the plugin from reading a plugin or theme folder or from writing the temporary ZIP. Check your PHP or web server error log for the message, then ask your host to add the WordPress path and your temporary directory to the allowed paths.

### 5. Raise the memory limit for large downloads

If the error only happens with **Download all** or with very large plugins, the process may be running out of memory. [Increase your WordPress memory limit](https://wordpress.org/support/article/editing-wp-config-php/#increasing-memory-allocated-to-php) and retry. See [fixing Download all failures on large sites](https://wpfactory.com/docs/download-plugins-and-themes/) for the full guidance.

### 6. Confirm filesystem permissions

The web server user needs read access to `wp-content/plugins/` and `wp-content/themes/` and write access to the temporary directory. If permissions were changed during a migration, restore them to your host's defaults.

### Still failing?

Copy the exact error from your server log, along with your plugin version, WordPress version and host, then contact the [Download Plugins and Themes support forum](https://wpfactory.com/support/item/download-plugins-and-themes-from-dashboard-wordpress-plugin/). For a corrupted or empty ZIP specifically, see [fixing a corrupted or empty ZIP download](https://wpfactory.com/docs/download-plugins-and-themes/).

Related articles

- [Fixing a Corrupted or Empty ZIP Download](https://wpfactory.com/docs/fix-corrupted-zip/)
- [Fix: Download All Fails or Times Out on Large Sites](https://wpfactory.com/docs/fix-download-all-large-sites/)
- [Fixing PHP 8.2 Deprecation Notices](https://wpfactory.com/docs/fix-deprecated-errors-on-php-8-2/)
- [Using Download Plugins and Themes on a WordPress Multisite Network](https://wpfactory.com/docs/plugin-not-working-on-wordpress-multisite-network/)
- [Bulk Download Plugins and Adding the Version to the ZIP Name](https://wpfactory.com/docs/bulk-download-plugins-themes/)

 

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