# Common Installation and Upgrade Errors

## Experiencing Issues With Databases

If you are experiencing issues right after installation of the plugin, or with databases, the issue is most likely rooted in an incompatible MySQL version on your server. 

Try upgrading MySQL to a compatible version (e.g. 8.x+) and run the installation / upgrade again.

### Example Errors

{% code overflow="wrap" %}

```
An exception occurred while executing a query: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '...' for key 'uniq.b2b_order_extension.order_id'
```

{% endcode %}