Web Connections have suddenly stopped working.

[anon97242]

Hello!

I have a web connection in a Dataflow that has suddenly stopped working. Within the data flow I get a message of "We could not evaluate this query due to invalid or missing credentials." 

When I look at Manage connections and attempt to connect to the connection I get:
Details: gatewy-onprem: The credentials provided for the Web source are invalid. (Source at url/rankings/endpoint.) Please have this information handy if you choose to create a support ticket. Session Id: 48ff8ba7-fae6-4269-b45e-224aaf9430c6 RequestId: cf5b7a0a-0095-4109-8fa8-538b1d77aad3 Cluster URI: https://api.powerbi.com Status code: 400 Time: Wed Jun 18 2025 15:50:07 GMT-0600 (Central Standard Time)

[v-kpoloju-msft]

Hi @anon97242 

Thank you for reaching out to the community. From the details you have shared, it looks like your Dataflow's web connection is failing due to a credentials issue. The error message:

We could not evaluate this query due to invalid or missing credentials.
The credentials provided for the Web source are invalid.

suggests that the service is unable to authenticate with the web endpoint, possibly due to expired credentials, changes in authentication requirements, or connectivity issues with the on-premises gateway.

Here are a few steps you can follow to troubleshoot and resolve the issue: Check if the Web Endpoint is Still Accessible: Please confirm that the endpoint (url/rankings/endpoint) is still reachable and returning the expected response (HTTP 200) from the machine where your on-premises data gateway is installed. You can test this using a browser or a tool like Postman or curl.

Re-enter or Update Credentials: Go to the Power BI Service > Manage Connections and Gateways. Locate your Web connection and choose Edit Credentials. Re-authenticate using the correct method (e.g., Anonymous, Basic, OAuth2, or API key). Sometimes, APIs that previously allowed anonymous access may begin requiring credentials, so it's worth double-checking.

Check the Gateway Health and Connectivity: Since the error includes a reference to gateway-on prem, make sure: Your on-premises data gateway is online and up to date. It has network access to the Web URL. The gateway service is running without errors. You can restart the gateway service as a quick first step if you're unsure.

Kindly refer to the below provided documentation links for better understanding:

Troubleshooting dataflow issues - connection to the data source - Power Query | Microsoft Learn
On-premises data gateway - Power BI | Microsoft Learn
Install an on-premises data gateway | Microsoft Learn
Add or remove a gateway data source - Power BI | Microsoft Learn

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[anon97242 · Accepted solution]

Thanks @v-kpoloju-msft 

After waiting overnight these seem to be working again so whatever session issue there was seems to have resolved itself. Would be greate if there was a "clear cache" mechanishm on the gateway.

For others looking I did try the following suggestions:
1)Re-enter or Update Credentials: Go to the Power BI Service > Manage Connections and Gateways. Locate your Web connection and choose Edit Credentials. Re-authenticate using the correct method (e.g., Anonymous, Basic, OAuth2, or API key). Sometimes, APIs that previously allowed anonymous access may begin requiring credentials, so it's worth double-checking. Was using anonymous, but this did not ever help. 

2) Rebuilding connection to the same URL did not create a new connection in the gateway, as the SessionID problem persisted

3) Check the Gateway Health and Connectivity: Since the error includes a reference to gateway-on prem, make sure: Your on-premises data gateway is online and up to date. It has network access to the Web URL. The gateway service is running without errors. You can restart the gateway service as a quick first step if you're unsure. Gateway was online and was able to access other URLs for the connection. Also verified the URL in question was live and was able to hit it from other machines