Hello everyone, I am using Altair Feko (version 2025.1) on Windows (64-bit).Recently I moved my simulation to a more powerful PC. I’m trying to run a simple dipole-antenna simulation (just a basic dipole), but the solver halts at startup: the GUI shows the “runfeko” command and then nothing proceeds — the simulation never starts. I’m attaching a screenshot of the GUI when it freezes. This setup used to work fine on my old machine, so I suspect the problem is related to the new environment or some setting change. Here are more details: * Model: simple dipole antenna * Feko version: 2025.1 (build 9597 from 2025-08-16) * OS / machine: Windows 64-bit on a new PC (more powerful than previous one) * What I expected: mesh generation and solver start, leading to simulation result. * What actually happens: solver does not start; run seems stuck immediately after launching runfeko. What I have tried / checked so far: * Verified that the .cfx model file is correct and identical to the one that previously worked. * Tried re-meshing / regenerating geometry (still stuck). * No obvious error message appears — the run window just remains blank / stalled. Could someone advise: * What kinds of causes may lead to Feko solver freezing / hanging before starting (especially when moving to a different PC)? * Are there recommended checks or logs to inspect (e.g. memory usage, compatibility issues, configuration settings) to diagnose this problem? * Could there be a license / permission / environment issue on the new PC that prevents solver execution? I’m willing to provide the model file or additional info if needed. Thank you in advance for your help.Best regards

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Error: Feko solver hangs / stops when running simple dipole simulation on new PC

Hello everyone,

I am using Altair Feko (version 2025.1) on Windows (64-bit).Recently I moved my simulation to a more powerful PC. I’m trying to run a simple dipole-antenna simulation (just a basic dipole), but the solver halts at startup: the GUI shows the “runfeko” command and then nothing proceeds — the simulation never starts. I’m attaching a screenshot of the GUI when it freezes.

This setup used to work fine on my old machine, so I suspect the problem is related to the new environment or some setting change.

Here are more details:

Model: simple dipole antenna
Feko version: 2025.1 (build 9597 from 2025-08-16)
OS / machine: Windows 64-bit on a new PC (more powerful than previous one)
What I expected: mesh generation and solver start, leading to simulation result.
What actually happens: solver does not start; run seems stuck immediately after launching runfeko.

What I have tried / checked so far:

Verified that the .cfx model file is correct and identical to the one that previously worked.
Tried re-meshing / regenerating geometry (still stuck).
No obvious error message appears — the run window just remains blank / stalled.

Could someone advise:

What kinds of causes may lead to Feko solver freezing / hanging before starting (especially when moving to a different PC)?
Are there recommended checks or logs to inspect (e.g. memory usage, compatibility issues, configuration settings) to diagnose this problem?
Could there be a license / permission / environment issue on the new PC that prevents solver execution?

I’m willing to provide the model file or additional info if needed.

Thank you in advance for your help.Best regards

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Jaehoon

Hello,

Please see my answers below

1.What kinds of causes may lead to Feko solver freezing / hanging before starting (especially when moving to a different PC)?

→ I don't think this is because the Feko model (.cfx) has some issue. If it had, the relevant error message would display.

2. Are there recommended checks or logs to inspect (e.g. memory usage, compatibility issues, configuration settings) to diagnose this problem?

→ Normally, some relevant messages are displayed in the Feko execution window which you already shared here. You might look into the .out file to see if any message is written.

3. Could there be a license / permission / environment issue on the new PC that prevents solver execution?

→ Yes, I have some concern here… about directory premission: I mean permission to the directory where the .cfx file is located and permission to the Temp directory. 1) Please try it with a different directory by moving the .cfx file 2) Check if the temp directory exists and you have enough permission to the temp directory. The Feko temp directory is defined in FEKOenvironmentFromSetup.lua under C:\Program Files\Altair\2025.1\feko as below.

Best regards,

Jaehoon

nepia

Hello again, and sorry for the delayed reply.

I moved the executable file and tried to run again, but I got the same error once more. Also, I can confirm that a temporary file is created, as shown in the screenshot below. Currently I am using a parameter-sweep macro to run the simulation, but the analysis halts midway due to the error I described previously. Immediately when it stops, a zero-size file with the extension “.lock” is generated.

I would appreciate any advice on how to deal with this issue.

Jaehoon

Hello,

It is normal that the ".lock" folder was generated.

However, what is not normal in your screen shot is that there was no .out file which was supposed to be generated after running the Feko solver for each .cfx file.

(It means that the Feko solver was not executed normally due to some reason.)

As you said, the issue mentioned in your first question still remains.

So I'd like to ask you to check the accessibility to the user directory and the temp directory (C:\temp) such as exisitence, permission or space. (Feko uses the temp directory as a scratch folder for writing/reading temporary data generated from the Feko solver.)

If you are unsure about this, please check it with your IT person.

Best regards,

Jaehoon

nepia

Hello

I have checked the access permissions for the temporary files and granted full access, but unfortunately this did not improve the situation.

Additionally, during a recent simulation run, I have occasionally encountered another error that is different from the one I reported earlier.

I would be grateful for any advice or suggestions on how to address these issues.

Feko caught signal 11 (PID 25068)

Segmentation violation

The following message from the server process (MYID= 22):

ERROR 3978: Internal Feko error. Please notify the Feko support team and provide the error number, preferably together with the Feko input and output files.

===================================================================================

= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES

= RANK 0 PID 33052 RUNNING AT CATENAR-3A4J47O

= EXIT STATUS: -1 (ffffffff)

===================================================================================

nepia

When I reinstalled the software, the following message appeared and I was unable to open CADFEKO. However, after restarting the computer again, the message no longer appeared.

Jaehoon

Hello,

Based on your sharing, it seems you are using a different memory system.

I mean "are you using a mapped memory, for example?" (mapped memory links a file's contents directly into a program's virtual address space).

I don't know why your Feko running hangs some time and why the running proceeds and generates some error the other time.

Which Feko version are you using?

We've fixed some mapped memory issues or some others until now. So I'd like to recommend you to install the latest Feko version, 2026.

Best regards,

Jaehoon

nepia

Hello

The version I am currently using is the latest one. When I moved Feko to another PC, it ran successfully on that machine, so the issue may be related to the original computer itself.

Thank you very much.