Solution :
To resolve this issue please check your connection string. If you need any further help with it then please check Connection Strings, which has the list of commonly used ones.
Please find below the commonly used Connection Strings:
1. SQL Server 2012
a. Standard Security
Server=myServerAddress;Database=myDataBase;User Id=myUsername;Password=myPassword;
b. Trusted Connection
Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;
c. Connection to a SQL Server instance
The server/instance name syntax used in the server option is the same for all SQL Server connection strings.
Server=myServerName\myInstanceName;Database=myDataBase;User Id=myUsername;Password=myPassword;
2. SQL Server 2005
a. Standard Security
Server=myServerAddress;Database=myDataBase;User Id=myUsername;Password=myPassword;
b. Trusted Connection
Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;
c. Connection to a SQL Server instance
The server/instance name syntax used in the server option is the same for all SQL Server connection strings.
Server=myServerName\myInstanceName;Database=myDataBase;User Id=myUsername;Password=myPassword;
3. MySQL
a. Standard
Server=myServerAddress;Database=myDataBase;Uid=myUsername;Pwd=myPassword;
b. Specifying TCP port
Server=myServerAddress;Port=1234;Database=myDataBase;Uid=myUsername;Pwd=myPassword;
4. Oracle
a. Using TNS
Data Source=TORCL;User Id=myUsername;Password=myPassword;
b. Using integrated security
Data Source=TORCL;Integrated Security=SSPI;
c. Using ODP.NET without tnsnames.ora
Data Source=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=MyHost)(PORT=MyPort)))(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=MyOracleSID)));User Id=myUsername;Password=myPassword;