Set Up the Microsoft SQL Server Connector: Server Name, SQL Express, Logins and Cloud

Connector setup · Microsoft SQL Server

Configurar el Microsoft SQL Server conector

Three things decide whether a SQL Server connection works: the right server name, a server that accepts network connections, and a SQL Server login. This page walks through each, plus Azure, Amazon RDS and Google Cloud SQL.

Aproximadamente 10 minutos Windows, Mac or Linux Agent Read-only, data stays put

Lo que obtendrás al final

A Microsoft SQL Server connection in Agentes de datos que pruebas Conectado, with the databases you want ticked, ready for Excel, Google Sheets, an AI assistant or the REST API. The Agent reads your data where it lives; nothing is copied into Query Streams.

Lo que necesita el agente

Añade la conexión

1. Open the form

   Abrir Agentes de datos (bajo Datos en el menú superior), haga clic Agregar conector on your Agent and choose Microsoft SQL Server. Database on Azure, Amazon or Google? Pick that provider’s own card instead; see the cloud sections below.

2. Fill in five boxes

   Nombre de la conexión

   Any name you will recognise, like Sales server.

   Servidor

   The server name, typed exactly as described in Find the server name. There is no Database box: you pick the database after the test.

   Puerto

   Dejar 1433, including for a named instance such as OFFICE-SERVER\SQLEXPRESS. The line under the box says the same: Leave 1433 for a named instance (host\INSTANCE); the server’s SQL Browser finds the port. Enter a port only if the instance uses a fixed one.

   Username / Password

   The SQL Server login. The boxes start empty.

   Dejar Tiempo de espera de conexión (segundos), Encrypt Connection y Trust Server Certificate as they are (why the last two do not matter today).

3. Click Test connection

   A green Conectado means the Agent signed in; the button changes to Siguiente. An amber Signed in means the login works but needs a database name: carry on, the next step asks for it (details). A red Connection failed comes with a message: find it in ¿La prueba falló?.

4. Pick the database and create

   Haga clic en Siguiente. Bajo Which databases do you want to work with? tick yours, click Siguiente, choose a Data realm, haga clic Siguiente, entonces Crear conector.

Test button greyed out? The Agent is offline: follow Is the Agent online? primero.

When something is in the way

Each section below is one situation, one action per step, with what you should see after it.

Find the server name

SQL Server can run several copies side by side on one computer, called instances. The first is usually the default instance and has no name of its own; any other, including every SQL Express install, has a name such as SQLEXPRESS. The Server box needs the computer and, for a named instance, the instance.

1. See which instances are installed

   On the SQL Server computer, click Start and type SQL Server Configuration Manager. If nothing appears, type the file name for your version and press Enter: SQLServerManager16.msc for SQL Server 2022, SQLServerManager15.msc for 2019, SQLServerManager14.msc for 2017, SQLServerManager17.msc for 2025. Click Sí if Windows asks for permission.

   In the list on the left click SQL Server Services. Each line that starts SQL Server ( is one instance. SQL Server (MSSQLSERVER) is the default instance. Anything else in the brackets, such as SQL Server (SQLEXPRESS), is a named instance, and that word is its name.

2. Find the computer’s name

   On the same computer click Start, entonces Configuración, entonces System, entonces About. The line Device name is the computer’s name, for example OFFICE-SERVER. Its IP address, such as 192.168.1.20, works too.

3. Or ask SQL Server itself

   If you have SQL Server Management Studio (SSMS), the Connect to Server box it opens with already shows the Server name people use. Once connected, click New Query, paste the line below and press F5:

   Paste into the query window, then press F5

   SELECT @@SERVERNAME;

   The result is the name in the right shape, for example OFFICE-SERVER\SQLEXPRESS.

4. Type it in the right shape

   What you have	Servidor	Puerto
   Default instance	OFFICE-SERVER o 192.168.1.20	1433
   Named instance (SQL Express)	OFFICE-SERVER\SQLEXPRESS	1433. This means “ask the server’s SQL Server Browser for the real port”.
   Named instance with a fixed port	OFFICE-SERVER	That port, for example 50123. Any port other than 1433 makes the Agent connect to that port directly and drop the instance name.
   A name with a comma, such as sql.example.com,14330	Paste it as it is	Dejar 1433; the port after the comma wins.
   A name with a colon, such as sql.example.com:14330	Paste it as it is	The Agent reads the colon as the comma SQL Server expects.
   SQL Server on the Agent’s own computer	localhost o localhost\SQLEXPRESS	1433. localhost means the Agent’s computer, not the one you are typing on.
   (localdb)\MSSQLLocalDB	Will not work, and the form says so under the box: LocalDB runs inside your Windows login session; the agent service cannot open it. Attach the database to a SQL Server or SQL Express instance and enter that server. Ask whoever built the app to move the database to SQL Server or SQL Express.

   As you type, a line under the Servidor box confirms how it was read:

   Named instance, Port 1433

   Named instance: the server’s SQL Browser finds the port. Leave Port at 1433.

   Named instance, another port

   A port other than 1433 is set, so the instance name is ignored: the agent connects to host,port. If you meant the instance, set Port back to 1433.

   A colon before the port

   Read as host,port. SQL Server separates the port with a comma; the agent accepts both.

   localhost, (local) or .

   localhost, (local) and . mean the computer the agent runs on, not this one.

   Reading named instances this way needs Agent 2.6.23 or newer (released 9 October 2026). Older Agents fail every named instance with Connection failed: Cannot establish TCP connection to SQL Server; the Agent updates itself, and this page covers one that has not.

If it is SQL Express or another named instance

A fresh SQL Express install accepts connections only from its own computer: TCP/IP, the setting that lets other computers in, starts turned off. A named instance also relies on a helper service, Explorador de SQL Server, to tell the Agent which port it is on. The steps below turn both on. You need to be an administrator on the SQL Server computer.

1. Open SQL Server Configuration Manager

   On the SQL Server computer, open it as in Find the server name, step 1. A window opens with a list on the left.

2. Look at TCP/IP for your instance

   In the list on the left, expand SQL Server Network Configuration y haga clic Protocols for SQLEXPRESS (your instance’s name after “for”). On the right are Shared Memory, Named Pipes y TCP/IP, each with a status. If TCP/IP already says Activado, skip to step 5.

3. Enable TCP/IP

   Right-click TCP/IP y elegir Enable. A message says the change only takes effect when the service restarts; click DE ACUERDO. The status now reads Activado, but nothing has changed yet.

4. Restart the instance

   In the list on the left click SQL Server Services. On the right, right-click SQL Server (SQLEXPRESS) y elegir Restart. The icon beside it shows a red square, then a green arrow, within a few seconds. Anyone using the database is disconnected for those seconds, so pick a quiet moment.

5. Set SQL Server Browser to start by itself

   In the same list find Explorador de SQL Server and read its Start Mode column. If it says Automatic, go to step 6. If it says Manual o Other (Boot, System, Disabled or Unknown), double-click Explorador de SQL Server, click the Service tab, set Start Mode a Automaticy haga clic DE ACUERDO.

6. Start SQL Server Browser

   If its State column does not say Running, right-click Explorador de SQL Server y elegir Start. The State changes to Running. Si Start is greyed out, step 5 did not save; do it again.

7. Open the firewall, if the Agent is on another computer

   A named instance needs two Windows Firewall rules on the SQL Server computer: UDP 1434 for the Browser and TCP for the instance’s own port. Open a firewall port on Windows: named instances shows how to read that port (under IPAll), make it fixed so it stops changing after a restart, and add both rules. Agent on the SQL Server computer itself? Skip this step.

8. Inténtalo de nuevo

   Back in the Portal, keep Servidor como OFFICE-SERVER\SQLEXPRESS y Puerto como 1433; the line under Server reads Named instance: the server’s SQL Browser finds the port. Leave Port at 1433. Haga clic en Inténtalo de nuevo. If you gave the instance a fixed port in step 7, you can instead type that port in Puerto; the Browser and the UDP rule are then not needed.

If the test says “Login failed” and the password is right

Many SQL Server and SQL Express installs accept only Windows accounts until one setting is changed, and the connector signs in with a SQL Server login. While that setting is off, the test says Connection failed: Login failed for user ‘qs_reader’. That is word for word what a wrong password gives, so it is easy to retype the password again and again. If you are sure of the password, this is the reason.

1. Open SSMS and connect

   On the SQL Server computer open SQL Server Management Studio. In the Connect to Server box leave Autenticación en Autenticación de Windows y haga clic Conectar. A panel called Object Explorer appears on the left with the server name at the top.

2. Open the server’s Security page

   Right-click the server name at the very top of Object Explorer and choose Propiedades. In the list on the left of the window that opens, click Seguridad. Bajo Server authentication there are two choices.

3. Allow SQL Server logins

   Si SQL Server and Windows Authentication mode is already selected, click Cancel: the setting is fine, so the login or password is wrong; go to step 5. Otherwise click it, then DE ACUERDO. A message says the change takes effect after SQL Server restarts; click DE ACUERDO.

4. Restart SQL Server

   Right-click the server name again, choose Restarty haga clic Sí. The icon by the server name turns grey and back to green in under a minute.

5. Make sure the login exists

   Ampliar Seguridad, entonces Logins. If the name you typed in the Portal is not listed, create it: Create a read-only database user: SQL Server has a paste-in version and a click-through one. Untick User must change password at next login; the Agent cannot change a password, so with that ticked it never gets in.

6. Inténtalo de nuevo

   Back in the Portal, click Inténtalo de nuevo. Conectado means you are through.

Encrypt Connection and Trust Server Certificate

Leave both boxes as they are. Today the Agent ignores them: it asks for no encryption and trusts whatever certificate the server shows. In practice:

• A server with a self-signed certificate connects without a certificate error. The Agent’s test never fails on a certificate today.
• A server that insists on encryption still gets it. Azure SQL always does; your own SQL Server does when its administrator has set Force Encryption.
• Otherwise the hop between the Agent and SQL Server is not encrypted, so it is best kept inside your own network. The Agent’s link to Query Streams is encrypted either way.

This is a known issue and is being fixed. SSMS on your own computer is different: if it says The certificate chain was issued by an authority that is not trusted, tick Trust Server Certificate in its Connect to Server box.

If your database is Azure SQL Database

1. Copy the server name

   En el Azure portal abierto Bases de datos SQL and click your database. Its overview page shows the full server name, such as myserver.database.windows.net. Copy it.

2. Let the Agent’s address through

   On the same page click Set server firewall. Set Public network access a Selected networks. Haga clic Add a firewall rule and enter the public IP address of the Agent’s computer (on that computer, search the web for “what is my IP”). Add your client IP adds the address of the computer your browser is on, which is only right if the Agent is on the same network. Click Guardar.

3. Use the Azure SQL card

   In the Portal choose Azure SQL instead of Microsoft SQL Server. In Azure, on your database’s page, open Cadenas de conexión y copie el ADO.NET one into Connection String (paste ADO.NET from the Azure portal); the boxes below fill in. It starts Server=tcp:; that tcp: is fine, the Agent drops it. Azure shows the password as {your_password}, so type the real one into Contraseña.

4. Name your database and test

   The Azure SQL card has a Base de datos box, because Azure ties each connection to one database. Type your database’s name, not master, luego haga clic Probar la conexión. Serverless databases pause when idle; the first test after a pause can take a minute.

If it is Azure SQL Managed Instance

A Managed Instance lives inside an Azure virtual network. Either install the Agent on a machine in that network and use the instance’s normal host name, or turn on its public endpoint:

1. Enable the public endpoint

   In the Azure portal open the SQL managed instance. Under Seguridad hacer clic Networking, elegir Enable for the public endpoint, and click Guardar.

2. Allow port 3342

   Your network administrator adds an inbound rule to the instance’s network security group: TCP, destination port 3342, source the Agent computer’s public IP, with a lower priority number than the deny_all_inbound rule.

3. Enter the public host name

   Bajo Configuración, Cadenas de conexión shows the public host, shaped name.public.zone.database.windows.net. In the Portal choose Microsoft SQL Server, put that host in Servidor y 3342 en Puerto (or paste name.public.zone.database.windows.net,3342 into Server and leave 1433), then test.

On any Azure host, a test without a database name can come back amber Signed in con This login needs a database name to sign in. even when the password is wrong. If Verificar then fails on a database you know exists, recheck the password.

If your database is Amazon RDS for SQL Server

1. Copy the endpoint

   En el Amazon RDS console elegir Bases de datos, click your SQL Server instance, and on the Conectividad y seguridad tab copy the Punto final and note the Puerto.

2. Let the Agent in

   Unless the Agent runs inside the same VPC, the instance needs Public accessibility empezar a Sí, and its VPC security group needs an inbound rule for that port from the Agent computer’s public IP. (My IP as the source fills in the address of the computer your browser is on.)

3. Use the Amazon RDS card

   In the Portal choose Amazon RDS and paste the endpoint with its port, such as mydb.abc123.us-east-1.rds.amazonaws.com:1433, into Endpoint or Connection String (paste from the RDS console). Port 1433 sets Database Engine a Servidor SQL; check it did, since the card starts on PostgreSQL. Username is the master username or a login you created. Then test.

If your database is Google Cloud SQL for SQL Server

1. Authorise the Agent’s address

   En el Cloud SQL instances page click your instance, then Conexiones in the menu, then the Networking tab. With Public IP ticked, under Authorized networks hacer clic Add network, put the Agent computer’s public IP in Red, haga clic Hecho, entonces Guardar.

2. Use the Google Cloud SQL card

   In the Portal choose Google Cloud SQL, set Database Engine a Servidor SQL, type the instance’s public IP (on its overview page) in Instance IP address, and change Puerto a 1433; it starts at 5432, PostgreSQL’s port. Running the Cloud SQL Auth Proxy on the Agent’s computer instead? Use 127.0.0.1.

After the test: pick the database

The connector has no Database box; the database is chosen on the step after a good test. What you see there depends on the login:

A list of databases

Bajo Which databases do you want to work with? tick yours. System databases such as master carry a system chip and are never ticked for you. You can tick up to five; the first is the Primary, used when a query does not name a database.

“This login can’t list databases”

Type the name in Type a database name y haga clic Verificar. You should see Sales added. (with your database’s name). Sales doesn’t exist or this login can’t open it. means a typo, or the login has no user in that database; What the agent said shows SQL Server’s own words, and the read-only login page shows how to map the login to it.

An amber “Signed in” after the test

The test says No database opened yet. Name it on the next step. followed by This login needs a database name to sign in. Enter your database. (Azure) or Signed in, but this login’s default database can’t be opened. Enter your database. Nothing is broken. Click Siguiente, type the database name and click Verificar.

Then click Siguiente, choose a Data realm, haga clic Siguiente, check the summary and click Crear conector. The Agent then reads the table list of each ticked database.

¿La prueba falló?

The message after Connection failed tells you which of these it is. Names in capitals stand for yours.

Siguiente: usar los datos

• Microsoft SQL Server to Excel
• De Microsoft SQL Server a Google Sheets
• SQL Server in Claude and other AI assistants (MCP)
• SQL Server as a REST API

Guías relacionadas

• Create a read-only database user
• Open a firewall port on Windows
• Is the Agent online?
• Instalar el agente en Windows
• Todas las guías