Understanding Error -40 in Datalogics Products

Overview

Error -40 is a licensing-related error primarily documented in the Adobe PDF Library (APDFL). It surfaces during initialization or activation and prevents the library from running. Other Datalogics products that share the same eval.lic / RLM licensing mechanism may also encounter similar licensing errors.

There are two known causes of this error in APDFL.

Affected Products

Adobe PDF Library (APDFL) — primary product where Error -40 is documented
Other Datalogics products using the eval.lic / RLM licensing system (e.g., PDF2IMG) may exhibit similar licensing errors

Cause 1: Activation Failure

This variant of the error presents as:

Error -40 requesting activation 
Please contact evalsupport@datalogics.com for further assistance.

This occurs when APDFL is unable to successfully activate, most commonly during evaluation. It has been observed on macOS GitHub Actions CI runners, and intermittently on Windows and Linux as well.
It has also been reported when running large numbers of simultaneous threads (e.g., 99 threads) on an evaluation version of APDFL.

Resolution

Ensure a valid license file (eval.lic) is present and correctly configured (see License File Setup below).
If the error occurs intermittently in CI/CD pipelines, consider staggering workflows to prevent all platforms from hitting the activation server simultaneously.
Contact Datalogics at evalsupport@datalogics.com if the issue persists.

Cause 2: System Clock Rollback

This variant presents as:

License error: System clock has been set back (-40)

This is triggered when the system clock has been set back, which violates the licensing mechanism used by APDFL, even if the current system time appears correct.

Resolution

Verify that the system clock is accurate and has not been manually or automatically adjusted backward.
Obtain and apply a fresh eval.lic file from Datalogics support.

License File Setup

In both cases, ensuring the `eval.lic` file is correctly placed is critical. This applies to APDFL and any other Datalogics product using the RLM licensing system. There are two accepted methods:

Method 1: Place the file in the working directory

For Adobe C/C++: Place eval.lic in the current working directory when running samples.
For Modern C++: Place eval.lic in the lib directory.
For DLE: Place eval.lic in the directory containing DL180PDFLPINVOKE.dll and com-datalogics-DL180PDFL.dll.

Method 2: Set the `RLM_LICENSE` environment variable (recommended)

On Windows:

set RLM_LICENSE=C:\Datalogics\Licenses\eval.lic

On Linux/macOS:

export RLM_LICENSE=/path/to/eval.lic

Additional Notes

The underlying license error code 0x4000000D (Error Code 13: genErrLicense) is a related license management error that can appear alongside or instead of Error -40 in some APDFL environments.
The eval.lic file is time-limited and will expire on the date shown inside the file (it is a plaintext file viewable in any text editor). A new license file must be obtained from Datalogics before expiration. This applies to all products using the eval.lic system.
Other Datalogics products such as PDF Alchemist have documented related license expiry errors (e.g., License has expired (-3), No license for product (-1)) using the same licensing infrastructure, suggesting that the RLM licensing system is shared across multiple products.

Contact

For licensing assistance with APDFL or any other Datalogics product, contact us at evalsupport@datalogics.com and/or tech_support@datalogics.com.