Character set 'utf8mb3' is not supported by .Net Framework error

[emanueleravasi]

Hello, 

I have a BI with a dataset connecting to a mysql v8 database. Everything is perfect while using BI Desktop: no problem when I refresh the data, no problem in publishing to BI Service. I installed and configured an On Premise Gateway on the server that hosts mysql 8 (Windows Server OS) and configured correctly the connection on BI Service (tested). But when I try to refresh the data, this is the error I get:

Data source error[ValidateMarkupTags]{"error":{"code":"DM_GWPipeline_Gateway_MashupDataAccessError","pbi.error":{"code":"DM_GWPipeline_Gateway_MashupDataAccessError","parameters":{},"details":[{"code":"DM_ErrorDetailNameCode_UnderlyingErrorCode","detail":{"type":1,"value":"-2147467259"}},{"code":"DM_ErrorDetailNameCode_UnderlyingErrorMessage","detail":{"type":1,"value":"[ccon]Si è verificato un errore durante la lettura dei dati dal provider: 'Character set 'utf8mb3' is not supported by .Net Framework.'[/ccon]"}},{"code":"DM_ErrorDetailNameCode_UnderlyingHResult","detail":{"type":1,"value":"-2147467259"}},{"code":"Microsoft.Data.Mashup.ValueError.DataSourceKind","detail":{"type":1,"value":"MySql"}},{"code":"Microsoft.Data.Mashup.ValueError.DataSourcePath","detail":{"type":1,"value":"[ccon][ccon][REDACTEDIP]</ip>[/ccon]<ip><ip>[REDACTEDIP]</ip></ip>;[redacted databasename][/ccon]"}},{"code":"Microsoft.Data.Mashup.ValueError.Reason","detail":{"type":1,"value":"DataSource.Error"}}],"exceptionCulprit":1}}} Table: dp_tickets.

Sometimes the "table:" is dp_tickets, sometimes it's a different table. I already converted en masse the charset for the entire db and checked twice that now every field and every table are utf8mb4.
I tried the latest mysql connector as well the 8.0.28 version (uninstall, install different version, restart the gateway service). Downgrading to a lower mysql version is not an option.

I tried deleting and re-publishing the BI (after changing the charset in mysql): nothing, same error.
I read and tried the solutions that I found in other tickets here but nothing worked.
What else can I do?

[v-saisrao-msft]

Hi @emanueleravasi,

Could you please confirm that you have submitted the support ticket to resolve your issue?

Thank you.

[emanueleravasi]

I submitted a ticket and I'm waiting for an answer. I'll keep you updated.

[v-saisrao-msft]

Hi @emanueleravasi,

I wanted to check if your issue was resolved after you raised the support ticket.

Thank you.

[v-saisrao-msft]

Hi @emanueleravasi,

Thank you @lbendlin @GilbertQ, for your valuable insights.
Below is a solved reference for the issue you’re facing. Please refer to the links for more details:
MySQL Bugs: #113715: Character set 'utf8mb3' is not supported by .Net Framework
Solved: Refresh data error: Character set 'utf8mb3' is not... - Microsoft Fabric Community

If this post helps, then please consider Accept it as a solution to help the other members find it more quickly.

Thank you.

[emanueleravasi]

Unfortunately, none of those links helped. I found those a few days ago. Thank you anyway.

[v-saisrao-msft]

Hi @emanueleravasi,

Since you've confirmed that the database and tables are set to utf8mb4, tested with a fresh setup, and are using the latest gateway version, but the Power BI Service is still showing the 'utf8mb3' is not supported by .NET Framework' error, this issue may require a more in-depth investigation from the backend.

Below is the link to raise the support ticket:

How to create a Fabric and Power BI Support ticket - Power BI | Microsoft Learn

Thank you.

[emanueleravasi]

Thank you, I submitted a ticket and I'm waiting for an answer.

[lbendlin]

Can you test with a separate database with a single table?

[emanueleravasi]

Hi Ibendin,

I just created a new database from scratch with a single table on the same virtual where the other database is. Collation: utf8mb4.

I created a new pbix, uploaded it to BI Service, configured the connection, etc.

I have the exact same error: 'Character set 'utf8mb3' is not supported by .Net Framework.'

[lbendlin]

If you have a Pro license you can open a Pro ticket at https://admin.powerplatform.microsoft.com/newsupportticket/powerbi
Otherwise you can raise an issue at https://community.fabric.microsoft.com/t5/Issues/idb-p/Issues .

[GilbertQ]

Hi @emanueleravasi 

Can you make sure that you have got the latest version of the standard gateway installed?

[emanueleravasi]

It's a fresh install: version 3000.274.3 (June 2025).