Connection string Error

Mohamed Rafi

4y1.1kLearn iOS Programming

3 Replies

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Gajendra Jangid4y ago
1. SqlConnection conn = new SqlConnection();
2. conn.ConnectionString = "Data Source=.;Initial Catalog=testDB;User id=root;Password=mysql";
3. if (conn.State != ConnectionState.Open)
4. conn.Open();
+1

Satya Karki4y ago

Hi, If your database is MSSQL then you can troubleshoot by checking the following:

1. make sure your SQL Server instance/ SQL Server Services is running.

2. make sure TCP/IP is enabled. This you can do from SQL Server Manager. Also, check Default port:1433
3. Make sure the firewall is not blocking the SQL Server.

4. Enable Remote Connection in SQL Server Properties.

Details are available below the article.

https://www.c-sharpcorner.com/article/resolve-error-40-could-not-open-a-connection-to-sql-server/

Muhammad Imran Ansari4y ago

It seems your data source is not correct, check your data source name or If database is on your local machine try the following:

SqlConnection conn = new SqlConnection();
conn.ConnectionString = "Data Source=.;Initial Catalog=testDB;User id=root;Password=mysql";
if (conn.State != ConnectionState.Open)
    conn.Open();