Data gateway & Custom connector

[Anonymous]

I'm pretty new in the creation of a custom connector but I was able to build something which works in power bi desktop
Now, I would like to make some refresh online, so I follow the following tuto:
Custom Data Connector: How to Deploy and Test - Microsoft Fabric Community

my .mez files is well deployed on my server 

In Power BI Services, I go in manage gateway, there I'm able to select the gateway that I deployed on my server; but when I try to create the connection, it is returning the following error message:

Unable to create connection for the following reason:
Unable to connect the data source. Either the data source is inaccessible, a connection time out occured or the data source credentials are invalid. Please verify the data source configuration and contact a data source administrator to troubleshoot this issue.

Details:

Test-GateWay: We cannot convert the value null to type Logical.

The only settings required by my connection is the api url, everything is working perfectly in Power BI desktop but not in services

Any idea of how could I try to debug that?

Many thanks in advance for your help 

[lbendlin]

install Power BI Desktop on that gateway cluster member, put the .mez in the desktop folder too, and then try to connect to your API from there.

[Anonymous]

With Power BI Desktop, it is working on our local machine
The idea here, is to check if the machine on which the gateway is installed had access to the api, correct ?

[lbendlin]

yes.  Your local machine is not part of the scenario.

[Anonymous]

Thank you for your time
I installed it on the machine on which the gateway is running and there, I have no issue with it
So probably I have to check on the second part of the message :
Test-GateWay: We cannot convert the value null to type Logical.

No?

[lbendlin]

You are using AAD authentication, right?

[Anonymous]

Sorry for the delay
The authentification method is set to anonymous for this connector