windows search service

Indexing Service is deprecated and removed in newer Windows versions. It has been replaced by Windows Search Service, which works in a completely different way. You cannot use it as a drop-in replacement.

So yes, you must change your application code.

What changed?

How to use Windows Search in your application

You query Windows Search using OLE DB (ADO.NET) or Shell APIs, not the old Indexing Service APIs.

Recommended approach (OLE DB – most common)

Use System.Data.OleDb to query the Windows Search index.

Example query:

using System.Data.OleDb;

var connection = new OleDbConnection(
    "Provider=Search.CollatorDSO;Extended Properties='Application=Windows';");

connection.Open();

var command = new OleDbCommand(
    "SELECT System.ItemName, System.ItemPathDisplay FROM SYSTEMINDEX WHERE System.ItemName LIKE '%report%'", 
    connection);

var reader = command.ExecuteReader();
while (reader.Read())
{
    var name = reader["System.ItemName"];
    var path = reader["System.ItemPathDisplay"];
}

What you need to change in your project

Remove all Indexing Service (COM) references
Add reference to System.Data
Rewrite search logic using Windows Search SQL syntax
Ensure Windows Search Service is running

Enable Windows Search Service

1. Open services.msc

2. Start Windows Search

3. Set Startup type = Automatic

Important limitations

• Windows Search only indexes configured locations

• Network folders must be explicitly indexed

• Indexing behavior is controlled by Indexing Options

Summary

• Indexing Service cannot be reused

• Windows Search is the supported replacement

• Requires code changes

• Query using OLE DB / SQL syntax

This is the correct migration path when moving to newer Windows Server versions.