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Version: Version 4.4

Install the PDF Toolbox SDK

Depending on the language you want to use, the PDF Toolbox SDK can be installed in various ways.

Steps to install the PDF Toolbox SDK:

  1. Install the package.
  2. Set a color profile.
  3. Install fonts.
  4. Set the license key.
  5. Locate the temp files directory and cache directory.

Install the package

Select the interface language of the library for specific instructions on how to install the package.

NuGet package

NuGet is a package manager that facilitates the integration of libraries for software development in .NET. The NuGet package for the PDF Toolbox SDK contains all the libraries needed, managed and native, for all supported operating systems.

You can get the NuGet package PdfTools.PdfToolbox.4.0.1.nupkg directly from or download it from the Pdftools website. In Microsoft Visual Studio, this is the default location for downloading packages.

The PdfTools.PdfToolbox.4.0.1.nupkg package contains .NET libraries with version .NET Standard 2.0, and native libraries for Windows, macOS and Linux.

The required native libraries are loaded automatically. All project platforms are supported, including AnyCPU.

To use the SDK, you need to register your license key.


This NuGet package is only supported on a subset of the operating systems supported by .NET Core. See operating systems

Install color profiles

Most systems have pre­installed color profiles available. If no color profiles are available, default profiles for both RGB and CMYK are generated on the fly by the PDF Toolbox SDK.

Color profiles can also be downloaded from the following websites:

For device RGB colors, a color profile sRGB Color Space Profile.icm, and for device CMYK, a profile USWebCoatedSWOP.icc are searched for in the following directories (recursively, in the order specified).

To install a color profile, download and copy the profile to the corresponding folder:

  1. %SystemRoot%\System32\spool\drivers\color
  2. Directory Icc, which must be a direct sub­directory of where the PdfToolboxAPI.dll resides.

Temp files directory

This directory for temporary files is used for data specific to one instance of a program. The data is not shared between different invocations and deleted after termination of the program.

The directory depends on the operating system. The product checks for the existence of environment variables in the following order and uses the first path found:

  1. The path specified by the %TMP% environment variable.
  2. The path specified by the %TEMP% environment variable.
  3. The path specified by the %USERPROFILE% environment variable.
  4. The Windows directory.

Cache directory

The cache directory is used for data that is persisted and shared between different invocations of a program. The actual caches are created in subdirectories. The content of this directory can safely be deleted to clean all caches.

This directory should be writable by the application. Otherwise, caches cannot be created or updated and performance degrades significantly.

  • If the user has a profile: %LOCAL_APPDATA%\PDF Tools AG\Caches
  • If the user has no profile: <TempDirectory>\PDF Tools AG\Caches