SQL Database: Authentication Issue After Visual Studio Update — Ongoing Problem

Question

SQL Database: Authentication Issue After Visual Studio Update — Ongoing Problem

Dilip-3803 0

Problem description

I am experiencing an authentication problem with my Azure SQL Database after updating Visual Studio. The issue started immediately following the update on September 25, 2026, at 12:00 AM Pacific Time. My Visual Studio project can no longer authenticate to the database, but I have not provided the exact error message, client library error text, or details about the authentication method used.

Environment

Azure SQL Database; Visual Studio 2026; The problem appeared immediately after updating Visual Studio; Authentication method not specified; No specific resource names, region, or SKU provided.

What I've already tried

I have reviewed support guidance on SQL Database authentication failures, checked the connection string, and examined client library versions. I created a new minimal Visual Studio project referencing the same packages and connection settings to reproduce the issue. However, I have not succeeded in resolving the problem or determining the exact cause.

Current status

Currently, my Visual Studio project cannot authenticate to Azure SQL Database after the latest update. I am seeking assistance to identify the root cause, particularly regarding the authentication method, client library error details, and potential network or configuration issues.

Erland Sommarskog 137.9K Reputation points MVP Volunteer Moderator

2026-09-27T08:25:47.44+00:00

but I have not provided the exact error message, client library error text, or details about the authentication method used.

Please do that. Else you can only get a long AI-generated answers like David Aniebo's that tries to cover all bases.
Himaja Y 555 Reputation points Microsoft External Staff Moderator

2026-09-28T10:04:03.2966667+00:00

Hi @Dilip-3803 ,

Thank you for contacting Microsoft Support.

We have started reviewing the reported issue and noted that a request case has already been created. The relevant details are being reviewed, and we are coordinating internally as needed to drive the investigation forward.

We will keep you informed of any significant findings and provide an update as soon as more information becomes available.

Thank you for your patience and cooperation.

2 answers

Your answer

Erland Sommarskog 137.9K Reputation points MVP Volunteer Moderator

2026-09-27T08:25:47.44+00:00

but I have not provided the exact error message, client library error text, or details about the authentication method used.

Please do that. Else you can only get a long AI-generated answers like David Aniebo's that tries to cover all bases.
Himaja Y 555 Reputation points Microsoft External Staff Moderator

2026-09-28T10:04:03.2966667+00:00

Hi @Dilip-3803 ,

Thank you for contacting Microsoft Support.

We have started reviewing the reported issue and noted that a request case has already been created. The relevant details are being reviewed, and we are coordinating internally as needed to drive the investigation forward.

We will keep you informed of any significant findings and provide an update as soon as more information becomes available.

Thank you for your patience and cooperation.

Answer 1

Here is the error message I got.

Failed to authenticate the user in Active Directory (Authentication=ActiveDirectoryDefault).

Error code 0xUnknown

Failed to acquire access token for ActiveDirectoryDefault: Azure.Identity error: DefaultAzureCredential failed to retrieve a token from the included credentials. See the troubleshooting guide for more information. https://aka.ms/azsdk/net/identity/defaultazurecredential/troubleshoot

EnvironmentCredential authentication unavailable. Environment variables are not fully configured. See the troubleshooting guide for more information. https://aka.ms/azsdk/net/identity/environmentcredential/troubleshoot
WorkloadIdentityCredential authentication unavailable. The workload options are not fully configured. See the troubleshooting guide for more information. https://aka.ms/azsdk/net/identity/workloadidentitycredential/troubleshoot
ManagedIdentityCredential authentication unavailable. No response received from the managed identity endpoint.
VisualStudioCredential authentication failed: No installed instance of Visual Studio was found
VisualStudioCodeCredential requires the Azure.Identity.Broker package to be referenced from the project. VS Code Azure See the troubleshooting guide for more information. https://aka.ms/azsdk/net/identity/vscodecredential/troubleshoot
AzureCliCredential authentication failed: Azure CLI not installed
AzurePowerShellCredential authentication failed: Az.Accounts module >= 2.2.0 is not installed.
AzureDeveloperCliCredential authentication failed: Azure Developer CLI could not be found.
The BrokerCredential requires the Azure.Identity.Broker package to be referenced. See the troubleshooting guide for more information. https://aka.ms/azsdk/net/identity/brokercredential/troubleshoot

Answer 2

@Dilip-3803
Since the issue started right after the Visual Studio update, it is most likely related to how Visual Studio provides credentials to your application, rather than a problem with the Azure SQL Database itself. To identify the exact cause, please share the full error message and the authentication method used in your connection string, for example SQL authentication or Authentication=Active Directory Default.

If you are using Microsoft Entra authentication, such as Active Directory Default or Active Directory Interactive, the application uses the account signed in to Visual Studio when running locally. A Visual Studio update can sometimes expire or reset this sign-in. Please go to Tools > Options > Azure Service Authentication, confirm the correct account is selected, and sign in again if needed.

Please also check the version of Microsoft.Data.SqlClient in your project. Starting with Microsoft.Data.SqlClient 7.0, the Microsoft Entra authentication support was moved out of the core package. If your project was upgraded to 7.0 or later and uses any Entra authentication mode, you need to add the Microsoft.Data.SqlClient.Extensions.Azure NuGet package.

If you are using SQL authentication, please verify that your client IP address is still allowed in the server firewall rules, and that the login credentials are still valid.

For additional information, please refer to the following Microsoft documentation:
Connect to Azure SQL with Microsoft Entra authentication and SqlClient | Microsoft Learn
Troubleshoot connectivity issues and other errors with Azure SQL Database | Microsoft Learn

Kindly let us know if the above helps or you need further assistance on this issue.

Please do not forget to "up-vote" wherever the information provided helps you, this can be beneficial to other community members.