# ERROR Message: Object reference not set to an instance of an object **URL:** \ **Category:** Bug Reports\ **Created:** [September 26, 2023, 10:23pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122 "2023-09-26T22:23:48Z")\ **Posts on this page:** 19\ **Page:** 1
**Author:** ![FdoLorenzo](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@FdoLorenzo](https://prepomax.discourse.group/u/FdoLorenzo)\ **Post date:** [September 26, 2023, 10:23pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/1 "2023-09-26T22:23:48Z")
Dear all, I am encountering an error when loading a file created using 1.35 with the latest V 1.41. when I try to load the file I get the following error under Windows 10 and 11. ![image](https://global.discourse-cdn.com/free1/uploads/prepomax/original/2X/6/6cf59d3b972966fdf974babcb63f49f25e1e7151.png) I have no problems when loading a 3D shell file, or when loading a smaller file. Has anybody encountered the same issue ---
**Author:** ![FEAnalyst](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/feanalyst/32/688_2.png) [@FEAnalyst](https://prepomax.discourse.group/u/FEAnalyst)\ **Post date:** [September 27, 2023, 5:59am UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/2 "2023-09-27T05:59:17Z")
Well, PrePoMax grows so quickly that it’s often not possible to ensure backward compatibility. Try removing features from the model to see which one causes the error. You can also try opening the file e.g. in v1.4.0. ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [September 27, 2023, 6:51am UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/3 "2023-09-27T06:51:08Z")
I really put a lot of work lately to ensure backward compatibility. Could you share the .pmx file for me to see if I can fix it? You could try opening the file in v1.4.0 and if works save it. Then open it in version v1.4.1. ---
**Author:** ![FdoLorenzo](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@FdoLorenzo](https://prepomax.discourse.group/u/FdoLorenzo)\ **Post date:** [September 27, 2023, 12:31pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/4 "2023-09-27T12:31:36Z")
Dear all, I discovered after trying to open other models that if I saved the .pmx file with the results of the calculation in the file, it does not open and gives the error reported. However, if the file just has the mesh and boundary conditions it opens. I tried to send the files but the site indicates that the files cannot be larger than 8 MB. Any other option to send them. Matej I can send a link with the files so that you can download them. Thanks for the attention given to my post. Thanks for a great application! All the best! ---
**Author:** ![FEAnalyst](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/feanalyst/32/688_2.png) [@FEAnalyst](https://prepomax.discourse.group/u/FEAnalyst)\ **Post date:** [September 27, 2023, 12:32pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/5 "2023-09-27T12:32:50Z")
> [@FdoLorenzo](#): > > Any other option to send them You can just upload the files to some hosting website like WeTransfer, Dropbox or Google Drive and share the link here. ---
**Author:** ![FdoLorenzo](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@FdoLorenzo](https://prepomax.discourse.group/u/FdoLorenzo)\ **Post date:** [September 27, 2023, 12:39pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/6 "2023-09-27T12:39:07Z")
Here are the links to the files: > **[Google Drive: Sign-in](https://accounts.google.com/v3/signin/identifier?continue=https%3A%2F%2Fdrive.google.com%2Ffile%2Fd%2F1juAG_KH32Z9vztvONrwXklA3txtUrWGl%2Fview%3Fusp%3Ddrive_link&followup=https%3A%2F%2Fdrive.google.com%2Ffile%2Fd%2F1juAG_KH32Z9vztvONrwXklA3txtUrWGl%2Fview%3Fusp%3Ddrive_link&ifkv=AYZoVhcoGAymdMTsTd1-gyraxcYg9Pa779AolPyn8hv4k6fO8mcVoaAbR3HtCULohP1rmQ4BY2LTJw&osid=1&passive=1209600&service=wise&flowName=GlifWebSignIn&flowEntry=ServiceLogin&dsh=S-1258231559%3A1695818286783537&theme=glif)** > > Access Google Drive with a Google account (for personal use) or Google Workspace account (for business use). > **[Google Drive: Sign-in](https://accounts.google.com/v3/signin/identifier?continue=https%3A%2F%2Fdrive.google.com%2Ffile%2Fd%2F1LK4SzYNvJmuSrxogr7QEyCt3lYCWrIkH%2Fview%3Fusp%3Ddrive_link&followup=https%3A%2F%2Fdrive.google.com%2Ffile%2Fd%2F1LK4SzYNvJmuSrxogr7QEyCt3lYCWrIkH%2Fview%3Fusp%3Ddrive_link&ifkv=AYZoVhc2Z-m63bhZtYRC3odkikiwAY-Hi_jZ3IChSdRTNqgCtHF5U2xZ_NXnbfPnMU-hQeKWau2pjg&osid=1&passive=1209600&service=wise&flowName=GlifWebSignIn&flowEntry=ServiceLogin&dsh=S-50305974%3A1695818307726068&theme=glif)** > > Access Google Drive with a Google account (for personal use) or Google Workspace account (for business use). Let me know if you can open them and get the same error. Best regards, ---
**Author:** ![FEAnalyst](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/feanalyst/32/688_2.png) [@FEAnalyst](https://prepomax.discourse.group/u/FEAnalyst)\ **Post date:** [September 27, 2023, 12:44pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/7 "2023-09-27T12:44:41Z")
You have to set “Anyone with the link” in access settings first. ---
**Author:** ![FdoLorenzo](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@FdoLorenzo](https://prepomax.discourse.group/u/FdoLorenzo)\ **Post date:** [September 27, 2023, 1:00pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/8 "2023-09-27T13:00:53Z")
Apologies, Here are the links again: > **[3D-Loaded-Rod-Piston-thread-3-21.pmx](https://drive.google.com/file/d/1juAG_KH32Z9vztvONrwXklA3txtUrWGl/view?usp=sharing)** > > Google Drive file. > **[3D-long-rod-piston-half.pmx](https://drive.google.com/file/d/1LK4SzYNvJmuSrxogr7QEyCt3lYCWrIkH/view?usp=sharing)** > > Google Drive file. Best regards, F Lorenzo ---
**Author:** ![FdoLorenzo](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@FdoLorenzo](https://prepomax.discourse.group/u/FdoLorenzo)\ **Post date:** [September 27, 2023, 2:48pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/9 "2023-09-27T14:48:22Z")
Where you guys able to open the two files that I sent? Thanks! ---
**Author:** ![FEAnalyst](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/feanalyst/32/688_2.png) [@FEAnalyst](https://prepomax.discourse.group/u/FEAnalyst)\ **Post date:** [September 27, 2023, 3:03pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/10 "2023-09-27T15:03:11Z")
Yes, now they can be downloaded. ---
**Author:** ![FdoLorenzo](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@FdoLorenzo](https://prepomax.discourse.group/u/FdoLorenzo)\ **Post date:** [September 27, 2023, 3:10pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/11 "2023-09-27T15:10:05Z")
Thanks! Were you able to figure out what the issue is? Thanks! ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [September 28, 2023, 5:40am UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/12 "2023-09-28T05:40:02Z")
I can confirm that there is an error reading the file containing the results. I will fix the v1.4.1 version to be able to open the file but the results will probably be lost. The problem is that I cannot open the file in any previous PrePoMax version. You said it is an old v1.3.5 model but opening it in the v1.3.5 version gives me the info that the file was last saved in the v1.4.0 version (bottom of the image): ![image](https://global.discourse-cdn.com/free1/uploads/prepomax/original/2X/e/e825e1626027a6a92925dafae958ba661e9adb99.png) Opening it in release version v1.4.0 does not work. Did you use any of the developer versions? ---
**Author:** ![FdoLorenzo](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@FdoLorenzo](https://prepomax.discourse.group/u/FdoLorenzo)\ **Post date:** [September 28, 2023, 2:32pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/13 "2023-09-28T14:32:32Z")
Matej, thank you for your comments and help. I used 1.41dev for some time and 1.40dev. What is strange is that trying to open a 3D shells pmx problem that contains the results is not a problem. If the file does not have the results in it, it will open. If the file is small and has results, 1.41 will open it. It is with those files that have the results saved but are large \> 50 MB that it results in the error. Once again, Thanks Matej! ---
**Author:** ![FdoLorenzo](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@FdoLorenzo](https://prepomax.discourse.group/u/FdoLorenzo)\ **Post date:** [September 29, 2023, 8:15pm UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/14 "2023-09-29T20:15:24Z")
Dear Matej, I was checking the files that I have created and found something that may shed some light into what the issue could be. For the cases that give the error if you look in the files attached (if you can) the file does not have an imported geometry. I had some issues creating the mesh with Prepomax and tried using FreeCad or Netgen directly, and exported the mesh in .inp format, and opened it with Prepomax. did everything else to define materials, loading and boundary conditions and ran the file. Then I saved the solution. I tired them again today and I can open with 1.41 cases regardless of size if I have a geometry in the file. I do not know if this is the issue but it is what I discovered today. Thanks Matej! ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [September 30, 2023, 7:18am UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/15 "2023-09-30T07:18:25Z")
I can not figure out what really happened with your files. I prepared an updated version of the v1.4.1 release that can open the file you shared with the results, but the results are lost. Can you test the new version on other files you had problems with? ---
**Author:** ![FdoLorenzo](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@FdoLorenzo](https://prepomax.discourse.group/u/FdoLorenzo)\ **Post date:** [September 30, 2023, 11:14am UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/16 "2023-09-30T11:14:33Z")
Matej, I will give it a try and let you know. If I can get the files to open again, rerunning the file is the lesser of my problems. Thank you very much for your help! All the best Fernando Lorenzo ---
**Author:** ![FdoLorenzo](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@FdoLorenzo](https://prepomax.discourse.group/u/FdoLorenzo)\ **Post date:** [October 2, 2023, 1:51am UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/17 "2023-10-02T01:51:56Z")
It worked well! Thanks Matej! ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [October 2, 2023, 11:41am UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/18 "2023-10-02T11:41:25Z")
Grat, I am closing this topic. ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [October 2, 2023, 11:41am UTC](https://prepomax.discourse.group/t/error-message-object-reference-not-set-to-an-instance-of-an-object/1122/19 "2023-10-02T11:41:28Z")