# CalculiX failed to run with PrepoMax generated inp file **URL:** \ **Category:** Model setup\ **Created:** [February 20, 2026, 5:48pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796 "2026-02-20T17:48:54Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![Charles](https://avatars.discourse-cdn.com/v4/letter/c/6f9a4e/32.png) [@Charles](https://calculix.discourse.group/u/Charles)\ **Post date:** [February 20, 2026, 5:48pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/1 "2026-02-20T17:48:54Z")
I have a power Ubuntu computer. I want to use PrepoMax on my Windows computer to set up a model, generate inp file and run CalculiX 2.23 with the input file on the ubuntu computer with more cores. I installed Pardiso solver on the Ubuntu computer. The model I work on is a simple linear model. I tried a simple single part (a rectangular bar). It worked on both computers. I also tried a model with two simple parts with a contact (two rectangular bars). It worked as well. When I tried my large model, it converges in PrepoMax with force residual value very small (e.g. 0.00001). But it doesn’t converges with force residuals very very large (e.g. \> 100000). I checked the followings. 1. dimensions (basically modulus) 2. contact (swap them, and change adjustment from default to 0.01) 3. mesh refinement in contact area Any more hints about solution? Thanks very much. ---
**Author:** ![Calc\_em](https://avatars.discourse-cdn.com/v4/letter/c/43a26b/32.png) [@Calc\_em](https://calculix.discourse.group/u/Calc_em)\ **Post date:** [February 20, 2026, 5:52pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/2 "2026-02-20T17:52:52Z")
Can you share the file or at least some screenshots ? More information about your case would be needed to help - how it is loaded, constrained, and so on. ---
**Author:** ![Charles](https://avatars.discourse-cdn.com/v4/letter/c/6f9a4e/32.png) [@Charles](https://calculix.discourse.group/u/Charles)\ **Post date:** [February 20, 2026, 6:16pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/3 "2026-02-20T18:16:27Z")
Thanks. I put the compressed input file in my google drive and share it here [https://drive.google.com/file/d/1WWpEJxt3DJKXgXyT2jdJaK0XwYz7iWMi/view?usp=sharing](https://drive.google.com/file/d/1WWpEJxt3DJKXgXyT2jdJaK0XwYz7iWMi/view?usp=sharing). ---
**Author:** ![Charles](https://avatars.discourse-cdn.com/v4/letter/c/6f9a4e/32.png) [@Charles](https://calculix.discourse.group/u/Charles)\ **Post date:** [February 20, 2026, 6:25pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/4 "2026-02-20T18:25:34Z")
It is propeller with 4 blades and one hub. The connections are the contacts. The contact is set up by search with type contact. The load is centrifugal force. ![image](https://global.discourse-cdn.com/free1/uploads/calculix/original/2X/4/4a78145a300dc8f6f07210de4f51b33c6ed174f6.png) ---
**Author:** ![Charles](https://avatars.discourse-cdn.com/v4/letter/c/6f9a4e/32.png) [@Charles](https://calculix.discourse.group/u/Charles)\ **Post date:** [February 20, 2026, 6:26pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/5 "2026-02-20T18:26:51Z")
with PrepoMax, the outputs are, iteration 2 Number of contact spring elements=1979880 Using up to 4 cpu(s) for the stress calculation. Using up to 4 cpu(s) for the symmetric stiffness/mass contributions. Factoring the system of equations using the symmetric pardiso solver number of threads = 4 Using up to 4 cpu(s) for the stress calculation. line search factor=0.952208 Using up to 4 cpu(s) for the stress calculation. average force= 29.807911 time avg. forc= 29.807911 largest residual force= 0.000002 in node 466835 and dof 3 largest increment of disp= 7.185813e+00 largest correction to disp= 6.225417e-10 in node 151687 and dof 3 convergence the increment size exceeds the remainder of the step and is decreased to 0.000000e+00 Using up to 4 cpu(s) for the stress calculation. Job finished ---
**Author:** ![Calc\_em](https://avatars.discourse-cdn.com/v4/letter/c/43a26b/32.png) [@Calc\_em](https://calculix.discourse.group/u/Calc_em)\ **Post date:** [February 20, 2026, 6:44pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/6 "2026-02-20T18:44:12Z")
I see that you are using tied contacts. Try with tie constraints instead. ---
**Author:** ![Charles](https://avatars.discourse-cdn.com/v4/letter/c/6f9a4e/32.png) [@Charles](https://calculix.discourse.group/u/Charles)\ **Post date:** [February 20, 2026, 6:44pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/7 "2026-02-20T18:44:43Z")
If I run ccx\_2.23 in my ubuntu, I got the following. iteration 2 Number of contact spring elements=1979880 Using up to 4 cpu(s) for the stress calculation. Using up to 4 cpu(s) for the symmetric stiffness/mass contributions. Factoring the system of equations using the symmetric pardiso solver number of threads = 4 Using up to 4 cpu(s) for the stress calculation. line search factor=1.000000 Using up to 4 cpu(s) for the stress calculation. average force= 40.818114 time avg. forc= 40.818114 largest residual force= 417863.278156 in node 97735 and dof 2 largest increment of disp= 0.000000e+00 largest correction to disp= 0.000000e+00 ---
**Author:** ![Charles](https://avatars.discourse-cdn.com/v4/letter/c/6f9a4e/32.png) [@Charles](https://calculix.discourse.group/u/Charles)\ **Post date:** [February 20, 2026, 6:45pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/8 "2026-02-20T18:45:57Z")
Thanks. I will make a try. ---
**Author:** ![Charles](https://avatars.discourse-cdn.com/v4/letter/c/6f9a4e/32.png) [@Charles](https://calculix.discourse.group/u/Charles)\ **Post date:** [February 20, 2026, 7:18pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/9 "2026-02-20T19:18:09Z")
One more interesting thing I noticed, when I run CalculiX in ubuntu machine with inp file that in the output, it mentioned nonlinear analysis is requested which I don’t. I check \*STEP in the inp file, there is no value after STEP. STEP 1 \*WARNING reading \*STATIC: a nonlinear analysis is requested but no time increment nor step is specified the defaults (1,1) are used Static analysis was selected Newton-Raphson iterative procedure is active ---
**Author:** ![Calc\_em](https://avatars.discourse-cdn.com/v4/letter/c/43a26b/32.png) [@Calc\_em](https://calculix.discourse.group/u/Calc_em)\ **Post date:** [February 20, 2026, 7:53pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/10 "2026-02-20T19:53:37Z")
> [@Charles](#): > > it mentioned nonlinear analysis is requested which I don’t Any form of nonlinearity can trigger it. Contact (even tied) too. Non-default incrementation parameters are not always needed, but you can specify them in the step settings as Automatic incrementation. ---
**Author:** ![Charles](https://avatars.discourse-cdn.com/v4/letter/c/6f9a4e/32.png) [@Charles](https://calculix.discourse.group/u/Charles)\ **Post date:** [February 21, 2026, 6:07pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/11 "2026-02-21T18:07:50Z")
I have tried tie constraints. It works on windows with PrepoMax but not on ubuntu cxx; this times, it simply quickly and quietly finish (on output window) without results. I then tried something special. In Windows command window, I tried **cxx\_2.22\_dyanmic.exe job**. in ubuntu, **cxx\_2.23\_pardiso job**. The symptom is same. So I conclude that the same input file can work in Windows but not in ubuntu. This may relate to OS, solver library, and, more mysteriously, environment setting. I tested cases with no contact and cases with simple contact. Surprisingly, they all works fine on Windows and Ubuntu. So, I conclude that the contact in this special case is more sensitive. This is beyond my capacity. I would assume this is a special case and wouldn’t stop me work on other cases. ---
**Author:** ![JuanP74](https://avatars.discourse-cdn.com/v4/letter/j/b5a626/32.png) [@JuanP74](https://calculix.discourse.group/u/JuanP74)\ **Post date:** [February 22, 2026, 4:50pm UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/12 "2026-02-22T16:50:32Z")
> 7.53 \*ELSET > Keyword type: model definition > This option is used to assign elements to an element set. The parameter > ELSET containing the name of the set is required (maximum 80 characters), there are names longer than 80 chars. furthermore I recommend converting windows end-of-line (CR+LF) to linux end-of-line (LF), it could sometimes create unexpected behaviour. ---
**Author:** ![Charles](https://avatars.discourse-cdn.com/v4/letter/c/6f9a4e/32.png) [@Charles](https://calculix.discourse.group/u/Charles)\ **Post date:** [February 26, 2026, 5:27am UTC](https://calculix.discourse.group/t/calculix-failed-to-run-with-prepomax-generated-inp-file/3796/13 "2026-02-26T05:27:23Z")
Thanks Juan. No, there is name longer than 80 characters. And changing end-of-line doesn’t help. It might be due to the version difference or the way I compile Pardiso. However, when I run small scale case (e.g. bar or two bars), it works well. When contact is surface contact, the residual is very large that it keeps iterating. When the contact is constraint tie, it quickly finish the run with 0 displacement and stress in frd file.