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If you’re running a WordPress website and using Gravity Forms, one of the most trusted and widely-used form builder plugins, it can be incredibly frustrating when things stop working — especially when it comes to database updates and data entry migration.
Recently, many users have reported an error that looks like this when trying to update or migrate entry metadata:
Current status: Error Migrating Entry Meta: COLLATION 'utf8_unicode_ci' is not valid for CHARACTER SET 'utf8mb4'
If you’ve encountered this exact error or something very similar, don’t worry — you’re not alone. This is a common issue, especially on websites that have undergone database upgrades, migrations, or character set conversions. The good news is that the fix is relatively simple once you understand what’s going on behind the scenes.
Essentially, this means that your WordPress database — or more specifically, the Gravity Forms table in the database — is trying to use a collation (in this case, utf8_unicode_ci) that isn’t compatible with the character set currently used (utf8mb4).
Gravity Forms expects the database to be aligned with what WordPress is using — and if the collation doesn’t match, things like metadata migration will fail.
This usually happens due to misconfiguration in your WordPress wp-config.php file or a legacy setting that’s no longer appropriate for your database.
At the root of the issue is a line in your wp-config.php file that looks like this:
define('DB_COLLATE', 'utf8_unicode_ci'); This line forces WordPress to use the utf8_unicode_ci collation throughout your database operations. But modern WordPress versions (especially since version 4.2) have switched to using utf8mb4 as the default character set, and with it, compatible collations like utf8mb4_unicode_ci or utf8mb4_general_ci.
Having an old or incompatible collation set in your config file can cause database operations to fail — including those required by Gravity Forms when it attempts to store or migrate form entry metadata.
The Solution: Remove the Incorrect DB_COLLATE Definition
Here’s what you need to do to resolve the issue:
Step 1: Locate Your wp-config.php File
This file is found in the root directory of your WordPress installation — typically the same folder as wp-content, wp-admin, and wp-includes.
You can access it via:
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cPanel File Manager
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FTP/SFTP
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SSH (if you have shell access)
Step 2: Open the File in a Code Editor
Use any code editor like Notepad++, VS Code, Sublime Text, or your hosting provider’s file editor. Locate the following line:
This line explicitly sets the database collation to utf8_unicode_ci, which is not compatible with the modern utf8mb4 character set.
Step 3: Delete or Comment Out the Line
To remove the problem, you simply need to delete the line or comment it out like so:
Or remove it entirely.
Step 4: Save the File and Re-upload (if needed)
If you edited the file locally, make sure to re-upload it to your server, replacing the existing wp-config.php.
What Happens Next?
Once that line is removed, WordPress will revert to using the default collation for your database, which is usually automatically detected and set correctly — especially if your database is already running with utf8mb4.
This will allow Gravity Forms to complete the migration or updates it was attempting. The error should no longer appear, and your form submissions, entry meta, and other operations should begin working as expected.
