Important Notice Regarding libiomp5md.dll and Intel CPUs

Dear Valued Customers,

We want to bring to your attention an important issue that may impact the performance of our software on certain Intel CPUs, specifically those from the 12th generation and later, which utilize Performance and Efficiency cores.

Issue Details:

The recent releases of EEMS (v11.8 and v12.0) included a new version of the libiomp5md.dll dynamic link library (DLL) from Intel. However, we have identified an incompatibility with Intel CPUs that incorporate Performance and Efficiency cores. This incompatibility can lead to significantly reduced performance on these processors.

Affected CPUs:

Intel CPUs from the 12th & 13th generation that are equipped with both Performance and Efficiency cores.


We are continuing to research the issue to identify the root cause. In the meantime, we would like to offer a temporary workaround for affected users:

  1. Visit our website [] to download the updated setup packages for version 11.8 and 12.0 of our software.
  2. Run the installer for the appropriate version.
  3. Once the installation is complete, navigate to the root installation directory of our software on your computer.
  4. Locate the existing libiomp5md.dll file and rename it or move it to a different location. This step is recommended to keep a backup of the original file.
  5. You should see a directory labeled ‘intel_compatibility_dll’ in the installation folder which contains the updated libiomp5md.dll file.
  6. Copy the libiomp5md.dll from the ‘intel_compatibility_dll’ directory and paste it into the root installation directory (where your EFDC+ executable is located).

This workaround should help mitigate the performance issues you may be experiencing on Intel CPUs with Performance and Efficiency cores until we can provide a more comprehensive solution.