Power Query Online - '', hexadecimal value 0x14, is an invalid character.

Hi SergeiStPete ,

There are a few possible reasons why you are getting this error. Here are some things you can check and try to fix the issue:

Make sure that the OData endpoint is accessible and valid. You can test the endpoint in a browser or another tool like Postman to see if it returns the expected metadata and data.
Make sure that you have entered the correct credentials for the OData endpoint in Power BI Service. You can edit the credentials in the Data Source Settings under Settings > Datasets > Your Dataset Name > Data Source Credentials. You can also try to use different authentication methods, such as Basic, Anonymous, or OAuth.
Make sure that the OData endpoint supports the OData version that you are using in your query. Power BI Service supports OData versions 1.0, 2.0, 3.0, and 4.02. You can specify the OData version in your query by adding an option like [Implementation=“2.0”] to the OData.Feed function.
Make sure that there are no firewall or proxy settings that might be blocking or interfering with the connection to the OData endpoint. You can check your network settings and try to disable any firewall or proxy temporarily to see if that helps.

Troubleshooting OData sign-in errors in Power BI Desktop - Power BI | Microsoft Learn

Odata connection error from PowerBi services - Microsoft Fabric Community

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Community Support Team _ Rongtie

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