Hi Antonio Craveiro ,

What version of Studio + GS have you installed?

Please make reference to the related documentation Adding the TM to the Project

project.Credentials.AddCredential(new Uri(serverAddress), String.Format(
"user={0};password={1};type={2}", username, password, useWindowsSecurity ? "WindowsUser" : "CustomUser"));
project.UpdateTranslationProviderConfiguration(config);

Hi Antonio Craveiro ,

What version of Studio + GS have you installed?

Please make reference to the related documentation Adding the TM to the Project

project.Credentials.AddCredential(new Uri(serverAddress), String.Format(
"user={0};password={1};type={2}", username, password, useWindowsSecurity ? "WindowsUser" : "CustomUser"));
project.UpdateTranslationProviderConfiguration(config);

Patrick Andrew Hartnett 

I've tried with studio 2021 and 2022. We're using both CU7 and CU8 groupshare instances

Both don't work.

I've tried both overloads of AddCredential, with 2 and 4 parameters. And none works.

I've also tried adding before the server url "ps." like in this answer you gave: (+) Sdl Sdk Project Automation Use Template and PreTranslateFiles using Server Based Translation Memories - API Q&A - Translation Productivity - Language Developers - RWS Community

It still doesn't work.

I'm able to add the servers manually in studio. Just not programmatically through the API

To note that I pass null to user and password since I'm using windows authentication.

I paste my code just so you can confirm:

new TranslationProviderCascadeEntry
(
new TranslationProviderReference(new Uri("sdltm."+tmInfoEntry.FileName)),
tmInfoEntry.Update,
true,
true,
0
)
);

project.UpdateTranslationProviderConfiguration(projectInfo.TargetLanguages[0],tmConfig);

project.Credentials.AddCredential(new Uri("ps."+tmInfoEntry.Server), "user=null;password=null;type=WindowsUser");

project.UpdateTranslationProviderConfiguration(projectInfo.TargetLanguages[0], tmConfig);

Hi Antonio Craveiro , thank you for raising this issue; we are currently reviewing this.  Internal tracking nr. CRQ-33068

I will circle back to you once I have more info

similar issue reported here: community.rws.com/.../windows-authentication-against-groupshare-not-working-via-studio-2021-api