PDF Encrypt ActiveX DLL — Password-Protect PDFs

Overview

PDF Encrypt ActiveX DLL adds password protection to PDF files generated or processed by your Windows application. Set an open password for readers, an owner password for permissions, and decide whether recipients may print, copy, edit or annotate.

The component supports the encryption methods used by Adobe Acrobat, including 40-bit RC4, 128-bit RC4, 128-bit AES and 256-bit AES. It is a standalone DLL and does not require Acrobat or Reader on the target machine.

It is a good fit for document generators, report engines, billing systems and internal tools that must protect output before it leaves the application.

Features

Key features

Require a password before the PDF can be opened.
Set a separate owner password for permissions.
Choose 40-bit, 128-bit or 256-bit encryption.
Allow or block printing, copying, editing and annotations.
Detect whether a file is already encrypted.

Read page count and file size after loading.
Works with Win32 and Win64 processes.
Royalty-free distribution with a valid license.
Supports Windows XP – 11, Windows Server 2003 – 2016 (incl. R2).

Use cases

What you can build

Billing and statements

Protect invoices and statements with the customer's own password before delivery.

Report distribution

Let recipients read a report but prevent editing or copying.

Evaluation copies

Ship a protected preview that cannot be reprinted or reused.

Compliance workflows

Apply consistent encryption settings across every document your system emits.

Sample code

C# example

C#

using PDFEncryptX;

var pdf = new PDFEncryptX.EncryptLibClass();
pdf.SetLicenseKey("YOUR-LICENSE-KEY");

int loaded = pdf.LoadFromFile(@"C:\docs\report.pdf", "");
if (loaded == 1)
{
    int permissions = pdf.CreatePermissions(0, 0, 0, 1, 1, 1, 1, 1);

    int result = pdf.Encrypt(
        @"C:\docs\report-protected.pdf",
        2,
        permissions,
        "owner-password",
        "reader-password");
}

pdf.Close();

If you only need to remove protection, use PDF Decrypt ActiveX DLL; if you need both directions in one component, use PDF Security ActiveX DLL.

Supported languages and environments

C#
.NET
VB.NET
VB6
Delphi
C++ Builder
Visual C++
ASP
ASP.NET
PHP
Python
Java
VBScript
JavaScript
ColdFusion
Perl
PowerBuilder
VBA

More examples are available on request. Your project can use late binding, an imported type library, or P/Invoke where applicable.

Licensing: call SetLicenseKey() with the key you receive after purchase. Trial builds run with the limitation described above.

Interface reference

Main methods

The installer includes a complete interface reference and demo projects.

Method	Purpose
`SetLicenseKey(key)`	Unlock the component with your license key.
`LoadFromFile(path, password)`	Open a PDF. Returns 1 on success, 0 on failure, -1 if missing.
`IsEncrypted`	Check whether the loaded file is already protected.
`CreatePermissions(...)`	Build the permission mask for the output file.
`Encrypt(output, keyLength, permissions, ownerPwd, userPwd)`	Encrypt and save. Returns 0 failed, 1 success, 2 already encrypted.
`Close()`	Release the open document.

Pricing

One-time licenses Save 40%

Royalty-free distribution. Prices in USD; taxes and VAT are handled by our Merchant of Record at checkout.

Single developer

$77.95 ~~$129.95~~

1 developer, or 1 server deployment

Royalty-free distribution
32-bit and 64-bit builds
Email support

Buy license

Development team

$155.95 ~~$259.95~~

Your development team, up to 5 server deployments

Royalty-free distribution
32-bit and 64-bit builds
Email support

Buy license

Enterprise

$299.95 ~~$499.95~~

Unlimited developers, servers and applications

Royalty-free distribution
32-bit and 64-bit builds
Email support

Buy license

Need a custom build or an upgrade? Contact us. See the refund policy.

Free trial

Download PDF Encrypt ActiveX DLL

Install the trial, run the sample code, and evaluate the output on your own documents. The installer includes the component, demo application and documentation.

Version 4.20 · 7.11 MB
Trial limitation: Output PDFs are watermarked until licensed.
Runs on Windows XP–11 and Windows Server 2003–2016
Unlocks with your registration key after purchase

Download trial (.exe) Compare licenses

The full version and registration key are delivered by email after purchase.

FAQ

PDF Encrypt ActiveX DLL questions

Which encryption strengths are supported?

40-bit RC4, 128-bit RC4, 128-bit AES and 256-bit AES, matching the formats produced by Adobe Acrobat.

Can recipients open the file without Acrobat?

Yes. Any PDF reader that supports standard PDF encryption can open the protected file.

Is distribution royalty-free?

Yes. A valid license allows royalty-free distribution in an unlimited number of applications.

What is the trial limitation?

Trial output PDFs are watermarked. Calling SetLicenseKey() with a purchased key removes the watermark.

Tutorials

See it working in code

Often used together

Save 40%

PDF Security ActiveX DLL

Encrypt, decrypt and apply permissions to PDF files from a single Windows component.

from $119.95 ~~$199.95~~ View details →

Save 40%

PDF Decrypt ActiveX DLL

Remove owner-password restrictions and unlock PDFs your app is allowed to process.

from $77.95 ~~$129.95~~ View details →

PDF Split Merge ActiveX DLL

Split, merge and rotate PDF files by page range from Windows applications.

from $129.95 View details →

Evaluate PDF Encrypt ActiveX DLL on your own files.

The trial is free and does not require registration. See the output before you buy.

Download trial See pricing