Fix PHP File Upload Errors: move_uploaded_file() & is_writable() Restrictions Made Easy!

🔧 Fix PHP File Upload Errors: move_uploaded_file() & is_writable() Restrictions

Trying to upload a file in PHP but seeing this frustrating error?

Warning: move_uploaded_file(): Unable to move '/tmp/php123.tmp' to 'uploads/file.jpg'
Warning: is_writable(): open_basedir restriction in effect...

This guide will help you fix these errors with real solutions, working code, SEO tips, and AdSense-friendly formatting.

✅ Why These Errors Occur

• move_uploaded_file(): PHP can’t move the file due to permission or path issues.
• is_writable(): PHP’s open_basedir restriction blocks access outside allowed paths.

🚀 Step-by-Step Solutions

1. Check Folder Permissions

Ensure the target folder is writable by PHP.

chmod 755 uploads
// Or for full write access (not recommended for production)
chmod 777 uploads

2. Correct the File Path

Always use the correct absolute or relative path:

<?php
$uploadDir = 'uploads/';
$targetFile = $uploadDir . basename($_FILES["file"]["name"]);
move_uploaded_file($_FILES["file"]["tmp_name"], $targetFile);
?>

3. Fix open_basedir Restriction

This error means PHP is restricted from accessing paths outside of its allowed directory.

Solutions:

• Use directories within open_basedir allowed paths.
• Edit php.ini (if you have access):

open_basedir = /var/www/html/:/tmp/

Or if on shared hosting, contact your hosting provider to add your upload directory to the allowed paths.

4. Validate is_writable() Before Upload

<?php
if (is_writable('uploads/')) {
  move_uploaded_file($_FILES['file']['tmp_name'], 'uploads/' . $_FILES['file']['name']);
} else {
  echo "Upload folder is not writable.";
}
?>

📁 Full Working File Upload Example

<form action="upload.php" method="POST" enctype="multipart/form-data">
  <input type="file" name="file">
  <input type="submit" value="Upload">
</form>

<?php
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
  $uploadDir = 'uploads/';
  if (is_writable($uploadDir)) {
    $filePath = $uploadDir . basename($_FILES["file"]["name"]);
    if (move_uploaded_file($_FILES["file"]["tmp_name"], $filePath)) {
      echo "File uploaded successfully.";
    } else {
      echo "Failed to move uploaded file.";
    }
  } else {
    echo "Upload folder not writable.";
  }
}
?>

⚠️ Precautions to Avoid Upload Errors

• Set correct folder permissions
• Always check with is_writable() before upload
• Use secure filenames to avoid path traversal
• Do not use chmod 777 in production
• Use open_basedir safe paths

❓ FAQs

What causes move_uploaded_file() to fail?

Incorrect path, permission issues, or open_basedir restrictions.

How to fix is_writable() restriction?

Change php.ini or use allowed folders in open_basedir.

Can I fix this on shared hosting?

Yes, contact your hosting provider to allow your folder path.

🎉 Conclusion

Fixing file upload errors in PHP is all about folder permissions, valid paths, and PHP configuration. Use the solutions above and keep your code clean!