Power BI connection to SAP authentication invalid.

Hi LIZQQ, 
Thank you for reaching out to the Microsoft Fabric Community Forum.

Although the error is shown in Power BI Service, the connection is failing at the On-premises data gateway while authenticating with SAP. Power BI Service doesn’t connect to SAP directly; it relies entirely on the gateway.

Since the SAP connection also fails from Power Query, this confirms the issue exists before the Service layer. Please update the on-premises data gateway to the latest version, verify the SAP NetWeaver RFC SDK is installed on the gateway machine, and then clear and re-enter the SAP credentials in Power BI Service. Also ensure the authentication method matches what SAP expects. Once the gateway can successfully authenticate to SAP, the refresh should work as expected.

Refer these links:
1. https://www.microsoft.com/en-us/download/details.aspx?id=53127 
2. https://learn.microsoft.com/en-us/data-integration/gateway/service-gateway-update 
3. https://learn.microsoft.com/en-us/power-bi/connect-data/service-gateway-onprem 

Hope that clarifies. Let us know if you have any doubts regarding this. We will be happy to help.

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