These three functions will create DSN through code. One will create any system DSN, and other two function will create DSNs specifically for Access and SQL server.

Fist Function = SQL Server
PARAMETERS: DSNName = DSN Name
ServerName = Name of Server
Database = Database to Use
RETURNS: True if successful, false otherwise

EXAMPLE:
CreateSQLServerDSN "MyDSN", "MyServer", "MyDatabase"

Second Function = Access DSN
PARAMETERS: DSNName = DSN Name
DatabaseFullPath = Full Path to .mdb file
RETURNS: True if successful, false otherwise
EXAMPLE:
CreateAccessDSN "MyDSN", "C:\MyDb.mdb"

Third Function = System DSN
PARAMETERS: 'Driver = DriverName
ATTRIBUTES: 'Attributes; varies as a function 'of the Driver
EXAMPLE: Refer to Code Above

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Option Explicit

Private Declare Function SQLConfigDataSource Lib "ODBCCP32.DLL" _
(ByVal hwndParent As Long, ByVal fRequest As Long, _
ByVal lpszDriver As String, ByVal lpszAttributes As String) _
As Long Private Const ODBC_ADD_SYS_DSN = 4

Public Function CreateSQLServerDSN(DSNName As String, _
ServerName As String, Database As String) As Boolean

Dim sAttributes As String

sAttributes = "DSN=" & DSNName & Chr(0)
sAttributes = sAttributes & "Server=" &
ServerName & Chr(0)
sAttributes = sAttributes & "Database=" &
Database & Chr(0)
CreateSQLServerDSN = CreateDSN("SQL Server", sAttributes)
End Function

Public Function CreateAccessDSN(DSNName As String, _
DatabaseFullPath As String) As Boolean

Dim sAttributes As String
'TEST TO SEE IF FILE EXISTS: YOU CAN
'REMOVE IF YOU DON'T WANT IT
If Dir(DatabaseFullPath) = "" Then Exit Function

sAttributes = "DSN=" & DSNName & Chr(0)
sAttributes = sAttributes & "DBQ=" &
DatabaseFullPath & Chr(0)
CreateAccessDSN = CreateDSN("Microsoft Access Driver (*.mdb)", _
sAttributes)
End Function

Public Function CreateDSN(Driver As String, Attributes As _
String) As Boolean
CreateDSN = SQLConfigDataSource(0&, ODBC_ADD_SYS_DSN, _
Driver, Attributes)
End Function