SQL Server Connection Strings for Classic ASP

Last updated: August 25, 2026.

Classic ASP applications normally connect to SQL Server through ADO. Use a supported SQL Server driver, enable encryption, and keep credentials outside files that can be downloaded or committed to source control.

OLE DB connection with SQL authentication

<%
Dim connectionString, conn

connectionString = _
  "Provider=MSOLEDBSQL;" & _
  "Server=tcp:sql01.example.com,1433;" & _
  "Database=ApplicationDb;" & _
  "UID=app_user;PWD=replace_with_secret;" & _
  "Encrypt=Mandatory;TrustServerCertificate=No;"

Set conn = Server.CreateObject("ADODB.Connection")
conn.Open connectionString
%>

Windows authentication

connectionString = _
  "Provider=MSOLEDBSQL;" & _
  "Server=sql01.example.com;" & _
  "Database=ApplicationDb;" & _
  "Integrated Security=SSPI;" & _
  "Encrypt=Mandatory;TrustServerCertificate=No;"

The IIS application-pool identity must have permission to connect to SQL Server. This avoids storing a database password in the ASP application.

ODBC Driver 18 connection

connectionString = _
  "Driver={ODBC Driver 18 for SQL Server};" & _
  "Server=tcp:sql01.example.com,1433;" & _
  "Database=ApplicationDb;" & _
  "Uid=app_user;Pwd=replace_with_secret;" & _
  "Encrypt=yes;TrustServerCertificate=no;"

Connection checklist

• Install the selected driver on the IIS server and match its 32-bit or 64-bit architecture to the application pool.
• Use a dedicated login with only the permissions the application needs.
• Use a certificate trusted by the web server; do not disable certificate validation in production.
• Open the SQL Server port only between required hosts.
• Use parameterized ADODB.Command objects for values supplied by users.

Microsoft lists the available keywords in its OLE DB Driver connection-string reference.