sharpoint list doesn't connect to excel service via web browser

Question

I am running with an issue which caused me a lot of waste time in vain, I customized a SharePoint with InfoPath 2013 and connected it to an excel file(using excel service)to perform some complicated calculations, however, everything work greats for me while previewing the list in InfoPath , but when I use the browser it gives the below error, I have tried a lot of solution such as

disable loopback, please any suggested idea will be appreciated

"

An error occurred while trying to connect to a Web service. An entry has been added to the Windows event log of the server. Log ID:5566 Correlation ID:070c379e-eb34-e0d3-1079-0377d4e32d9c"

Answer 1

This issue occurs because loopback protection is always enabled in the SharePoint Online environment. Loopback protection must be disabled for InfoPath forms to be able to connect to some SharePoint Online web services. And thus, if the user is trying to publish an InfoPath form and that form tries to execute object model calls (REST and SOAP calls) while using the InfoPath Web Services then it will fail because loopback protection is enabled in SharePoint Online.

Check this KB article for more information about Error message when you connect an InfoPath form to a SharePoint Online web service: "An error occurred while connecting to a Web Service".

You would be better to get and display data using the Client Side Object Model (CSOM) instead of using InfoPath.