How to Use ReadInfo.dll in 64-bit Applications with C# (Using VeryPDF FileInfoCOM.exe) to read page count from SPL, PCL, PDF, PS, SPL-EMF, Spool files

A Complete Guide for Developers Working with PCL/PS/Spool File Analysis
If you plan to purchase and integrate our ReadInfo.dll technology but are concerned about 64-bit compatibility, this guide explains everything you need to know.

Although ReadInfo.dll itself is a 32-bit native library, we provide a powerful and convenient solution that works perfectly in both 32-bit and 64-bit applications, including modern C#/.NET environments.

To support all architectures, VeryPDF offers a COM-compatible wrapper called FileInfoCOM.exe, which exposes all functionality of ReadInfo.dll through a universal COM interface. This provides full compatibility with x86 and x64 applications, eliminating the limitations of loading a 32-bit DLL
directly into a 64-bit process.

In addition, many of our customers also benefit from our advanced page-counting SDK, which works directly with spool files and printer data streams:

VeryPDF Spool File Page Counter SDK

https://www.verypdf.com/app/hookprinter/spool-file-page-counter-sdk.html

This SDK is ideal for analyzing PCL, PostScript, EMF, SPL, and other print-related file formats.

Why Use FileInfoCOM.exe Instead of ReadInfo.dll?
Direct DLL loading requires matching architectures:

File Type	x86 App	x64 App
ReadInfo.dll	✔ Works	✖ Cannot load 32-bit DLL
FileInfoCOM.exe	✔ Works	✔ Works

Because ReadInfo.dll is compiled as 32-bit, a 64-bit application cannot load it directly through P/Invoke.

FileInfoCOM.exe solves this problem. It exposes all the same functions through COM automation, which can be called from any .NET version, including:

.NET Framework 2.0 – 4.8
.NET 5, .NET 6, .NET 7, .NET 8
Any CPU / x86 / x64 / ARM64 builds

This means you no longer need to worry about DLL architecture or interop complexity.

Step-by-Step Guide: Using FileInfoCOM.exe in C#
Step 1 — Register FileInfoCOM.exe (Administrator Required)
Open a Command Prompt with Administrator privileges and run:

FileInfoCOM.exe /regserver

Alternatively, double-click the provided script:

install.vbs

This registers the COM interface in the Windows registry.

Step 2 — Add COM Reference to C# Project
After registration:

Open your Visual Studio project
Go to Project → Add Reference
Select the COM tab
Choose FileInfoCOM
Click OK

Visual Studio will automatically generate an interop assembly (Interop.FileInfoCOM.dll).

Step 3 — Use FileInfoCOM.exe from C#
Below is a complete working example demonstrating how to read PCL file metadata such as:

Page count (black & white and color)
Page size (width and height)
Copy count
Paper size name
Rendering behavior

✔ Full Example Code

using System;
using FileInfoCOM;

namespace ParsingTest {
    class Program {

        static void Main(string[] args)
        {
            if (args.Length != 1)
            {
                Console.WriteLine("Usage:");
                Console.WriteLine("test.exe C:\\input.pcl");
                Console.WriteLine("test.exe C:\\input.ps");
                return;
            }

            string fileName = args[0];
            int bIsRenderToPDF = 0;
            int bwPageCount = 0;
            int colorPageCount = 0;
            int copyCount = 0;
            double nPageWidth = 0;
            double nPageHeight = 0;
            string strPaperSizeName = new string(' ', 300);

            FileInfoClass objFileInfo = new FileInfoClassClass();

            // Set license key
            objFileInfo.com_ReadInfoSetCode("XXXXXXXXXXXXXXXXXX");

            // Parse PCL/PS file information
            objFileInfo.com_ReadInfoFromPCLFile(
                fileName,
                bIsRenderToPDF,
                ref bwPageCount,
                ref colorPageCount,
                ref copyCount,
                ref nPageWidth,
                ref nPageHeight,
                ref strPaperSizeName
            );

            Console.WriteLine($"File: {fileName}");
            Console.WriteLine($"Render To PDF: {bIsRenderToPDF}");
            Console.WriteLine($"BW Pages: {bwPageCount}");
            Console.WriteLine($"Color Pages: {colorPageCount}");
            Console.WriteLine($"Copies: {copyCount}");
            Console.WriteLine($"Width: {nPageWidth}");
            Console.WriteLine($"Height: {nPageHeight}");
            Console.WriteLine($"Paper Name: {strPaperSizeName}");
        }
    }
}

This code runs identically on both 32-bit and 64-bit systems.

Advanced Page Counting for Print Management Systems
If you are analyzing spool files, printer data streams, or building:

Print accounting systems
Secure output management tools
Print job monitoring services
Billing & metering software
Workflow automation tools for enterprise printing

You may also need deeper access to SPL, PCL, PostScript, EMF, or XPS print data.

VeryPDF provides a specialized SDK for this purpose:
VeryPDF Spool File Page Counter SDK
https://www.verypdf.com/app/hookprinter/spool-file-page-counter-sdk.html

This SDK supports:

Accurate page counting without opening the file
Extraction of color/BW pages
Duplex/simplex detection
Paper size, orientation, scaling
Printer command stream parsing (PCL, PS, PDF, EMF, SPL, XPS)
Windows print spool monitoring

It integrates perfectly with the ReadInfoCOM workflow and is recommended if you are developing a full print-management or job-accounting system.

Conclusion
Although ReadInfo.dll is 32-bit, you can safely use all of its functions in any 64-bit C# application by calling our COM interface wrapper — FileInfoCOM.exe.

This provides: