---
title: "Fixing Dependency Check errors"
url: https://phatdev.net/en/docs/sl-migrations/how-to-resolve-dependency-checks
lang: en
updated: 2026-10-20
alternate:
  vi: https://phatdev.net/docs/sl-migrations/how-to-resolve-dependency-checks
markdown: https://phatdev.net/en/docs/sl-migrations/how-to-resolve-dependency-checks.md
---

# Fixing Dependency Check errors

Part of the doc set: [SL Migrations](https://phatdev.net/en/docs/sl-migrations.md)

> The scanner reports a missing PHP extension or function.

## Dependency Checks Failed

The scanner found that the server is missing a required PHP extension or function → it blocks the build/restore.

## Required PHP extensions

- **ZipArchive** - packing the archive
- **openssl** - encryption tokens
- **mbstring** - string encoding
- **json** - config files
- **curl** - connecting to cloud storage
- **pdo_mysql** or **mysqli** - database
- **fileinfo** - detecting MIME types

## Check which extensions are installed

Create an `info.php` file in the web root:
```php
<?php phpinfo(); ?>
```

Open `https://example.com/info.php` → look for the extension name. **Delete the file when you are done** (it exposes server information).

## Install a missing extension

How to install depends on the hosting:
- **Shared hosting**: the common extensions are usually already there. If one is missing, contact support and ask them to install it.
- **VPS Ubuntu/Debian**: `apt install php-zip php-curl php-mbstring php-mysql php-xml`
- **VPS CentOS/RHEL**: `yum install php-zip php-curl php-mbstring php-mysqlnd php-xml`
- **cPanel**: WHM → PHP Extensions Manager
- **Plesk**: Tools & Settings → PHP Settings

After installing an extension, restart PHP-FPM (VPS) or wait a few minutes (shared hosting).

## Required PHP functions

The scanner also checks some functions:
- `exec()` - for the Shell Exec engine
- `shell_exec()`
- `escapeshellarg()`
- `set_time_limit()`
- `ini_set()`

Some hosts disable these functions through `disable_functions` in `php.ini`. If `exec` is disabled, you cannot use the Shell Exec engine - switch to **DupArchive**.

## ionCube / Suhosin

Some hosting providers have the ionCube Loader or the Suhosin patch, which can block some of the plugin's operations.

If the build fails and you find Suhosin is present → contact your hosting provider and ask them to whitelist the functions the plugin needs.

## WordPress version

The plugin requires WordPress >= 4.9 (6.0+ recommended). Update WordPress in wp-admin if your version is old.

## See also

- [Quick Start](https://phatdev.net/en/docs/sl-migrations/quick-start)
- [Scanner warnings](https://phatdev.net/en/docs/sl-migrations/how-to-resolve-scanner-warnings-errors-and-timeout-issues)