Power BI refresh Error: Requested value 'None' was not found.

[Suryamaxillian]

Requested value 'None' was not found.

This error is showing while refreshing the data from MySQL in PowerBI. All the schema, table and column names are correct. It is happened after Navigation step in power query.

[v-prasare]

Hi @Suryamaxillian,

We would like to confirm if our community members answer resolves your query or if you need further help. If you still have any questions or need more support, please feel free to let us know. We are happy to help you.

Thank you for your patience and look forward to hearing from you.
Best Regards,
Prashanth Are
MS Fabric community support

[v-prasare]

Hi @Suryamaxillian,

We would like to confirm if our community members answer resolves your query or if you need further help. If you still have any questions or need more support, please feel free to let us know. We are happy to help you.

@ANVS & @Mauro89 ,Thanks for your prompt response

Thank you for your patience and look forward to hearing from you.
Best Regards,
Prashanth Are
MS Fabric community support

[ANVS]

Hello @Suryamaxillian 

The issue your facing is due to the SQL connector version mismatch between the Power BI SQL Connector and MySQL .NET Connector in your machine and also the metadata mismatch between Power Bi and Source.

Possible Solutions are like below:
- Check the MySQL Connector version between the two.
- Clear and Reconnect the Data Source

• In Power BI Desktop, go to
  File → Options and settings → Data source settings → Clear Permissions,
  then reconnect to the MySQL source.

- Verify the Navigation steps:

• Open Power Query Editor → Advanced Editor.

• Check the Navigation step and remove any parameters or fields showing None.

- If the query still persists try the below:

Try disabling “Enable Native Database Queries” temporarily in Power Query.

😊 If this post helped you, feel free to give it some Kudos! 👍
✅ And if it answered your question, please mark it as the accepted solution.

[Mauro89 · Accepted solution]

Hi @Suryamaxillian 

That “Requested value 'None' was not found” error usually appears when Power Query encounters a metadata or type mismatch — often introduced after a schema or driver change in MySQL.

Common causes might be:

1. MySQL connector update or mismatch — sometimes the Power BI Desktop or Gateway driver version changes and the query references an outdated enum value.

2. Changed data type or column metadata — if any column type changed (especially enum, set, or timestamp), the connector may fail to map it correctly.

3. Navigation step caching — cached schema info from a previous session can cause this error after table renames or column changes.

Try these fixes

1. Rebuild the navigation step:

   • In Power Query, delete or temporarily disable the Navigation step.

   • Reconnect to your table again via Home → Recent Sources → MySQL and navigate to the same table.

   • Compare the auto-generated query to ensure the schema matches.

2. Update your MySQL connector:

   • Download the latest official MySQL .NET Connector (8.3+ recommended).

   • Restart Power BI Desktop afterward.

3. Clear Power Query cache:

   • Go to File → Options → Data Load → Clear cache.

   • Reopen your file and refresh.

4. Check special column types:

If your MySQL table includes enum or set fields, try casting them in SQL to varchar in a custom query:

SELECT CAST(enum_column AS CHAR) AS enum_column, ... FROM your_table;

Hope this helps you a bit.

Best regards!