# Problems importing .step and .stp files **URL:** \ **Category:** General Questions\ **Created:** [January 26, 2024, 6:25pm UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452 "2024-01-26T18:25:59Z")\ **Posts on this page:** 19\ **Page:** 1
**Author:** ![fatmac](https://avatars.discourse-cdn.com/v4/letter/f/b782af/32.png) [@fatmac](https://prepomax.discourse.group/u/fatmac)\ **Post date:** [January 26, 2024, 6:25pm UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/1 "2024-01-26T18:25:59Z")
I have just down loaded and installed v2.0.0 into C:Program Files. The installation appeared ok but now I can not import any step or stp files. I get some odd warnings about issues with fillets and others about the mesgher being busy. I have tried several files, some form the Models folder installed with the program. Stl files appear to import as expected. I have added an image of the error message ![image](https://global.discourse-cdn.com/free1/uploads/prepomax/original/2X/6/6d6f6590eb9576be26d6d400859e5b43e01b5e2c.jpeg) ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [January 26, 2024, 9:16pm UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/2 "2024-01-26T21:16:51Z")
Program Files is admin protected folder. Move PrePoMax to a folder which is not admin protected and it will work. ---
**Author:** ![fatmac](https://avatars.discourse-cdn.com/v4/letter/f/b782af/32.png) [@fatmac](https://prepomax.discourse.group/u/fatmac)\ **Post date:** [January 26, 2024, 9:54pm UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/3 "2024-01-26T21:54:02Z")
thank you for your rapid reply -I was aware of the admin issues in that folder and had been running the program as an administrator. I have now re-installed direct to the c: folder but still get the same errors. I also tried installing version v2.0.0.3 and that gives me similar issues - unv and stl files still import ok ![image](https://global.discourse-cdn.com/free1/uploads/prepomax/original/2X/5/5811a669235fdf8a6ea2a4e8a730c47525bdb9c5.png) ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [January 28, 2024, 4:31pm UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/4 "2024-01-28T16:31:15Z")
It seems the Netgen and its plugin for geometry import OCC is not working. Are you using a fresh Windows installation? Which version? ---
**Author:** ![fatmac](https://avatars.discourse-cdn.com/v4/letter/f/b782af/32.png) [@fatmac](https://prepomax.discourse.group/u/fatmac)\ **Post date:** [January 29, 2024, 2:18am UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/5 "2024-01-29T02:18:48Z")
Thanks again for the reply - I’m using W11. Since u last mail I have read the instillation guide more carefully (perhpas I should have started there!!) and see "extract the .zip file to a non-system directory " I was not really sure exactly what that meant but coupled with ur advice in the ur first reply, I extracted the .zip file to my documents and now it is working just fine!. I have noticed, however, that on a few occasions where I have managed to crash prepomax, that when I restart it I can not import and .stp file and get the same errors reported earlier - the problem disappears when I restart windows - all a bit odd but not a big issue for me as it has not happened very often. I must take this opportunity to say what a great program this is -I have not used it for some time but my interest got rekindled with some videos I saw about transfinite volume meshing. I am very impressed with the meshing capabilities of the program- a big step forward to what I have been using else where. ![image](https://global.discourse-cdn.com/free1/uploads/prepomax/original/2X/d/d426518f4c3a69767920a1baad2cc20ae97a7afb.png) ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [January 29, 2024, 6:49am UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/6 "2024-01-29T06:49:16Z")
Thank you for the comments. We indeed have some problems with PrePoMax crushing occasionally, especially at the start of its use. But unfortunately, the problem is out of my hands to fix. ---
**Author:** ![robertorosa](https://avatars.discourse-cdn.com/v4/letter/r/b4bc9f/32.png) [@robertorosa](https://prepomax.discourse.group/u/robertorosa)\ **Post date:** [February 7, 2024, 7:52pm UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/7 "2024-02-07T19:52:46Z")
Good morning, I have the same problem with Windows 11. I installed prepomax in c: , but it doesn’t import the step files ---
**Author:** ![fatmac](https://avatars.discourse-cdn.com/v4/letter/f/b782af/32.png) [@fatmac](https://prepomax.discourse.group/u/fatmac)\ **Post date:** [February 7, 2024, 10:49pm UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/8 "2024-02-07T22:49:40Z")
that was the same for me - once I installed into “Documents” it all worked just fine - hope u get it sorted ---
**Author:** ![robertorosa](https://avatars.discourse-cdn.com/v4/letter/r/b4bc9f/32.png) [@robertorosa](https://prepomax.discourse.group/u/robertorosa)\ **Post date:** [February 8, 2024, 2:57pm UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/9 "2024-02-08T14:57:20Z")
Thank you for your answer, I tried installing in the “DOCUMENTS” folder and also in other folders… I also tried different versions (v2.0.0 v1.4.0 v1.3.2) but I always have the same problem: … 02/08/24 15:33:47 The mesher is busy. …02/08/24 15:33:47 at PrePoMax.Controller.ImportBrepPartFile(String brepFileName, Boolean showError) …02/08/24 15:33:47 There were errors while importing the file/files. …until a month ago I had no problems even with different versions. Could it be a windows problem? or DLL? ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [February 9, 2024, 10:08am UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/10 "2024-02-09T10:08:43Z")
It seems there are problems with versions where Gmsh was added. I will have to check this in a freshly installed Win 11 environment, but it will take me some time to prepare it. Hopefully, I can reproduce the problem. ---
**Author:** ![robertorosa](https://avatars.discourse-cdn.com/v4/letter/r/b4bc9f/32.png) [@robertorosa](https://prepomax.discourse.group/u/robertorosa)\ **Post date:** [March 5, 2024, 6:48am UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/11 "2024-03-05T06:48:14Z")
> [@robertorosa](#): > > The mesher is busy After a bit of testing I think my “The mesher is busy” problem has been solved. I had to register the EXE file “NetGen\NetGenMesher.exe” in the DO NOT CHECK list in my antivirus (McAfee). After this operation the import of PrePoMax STEPs works perfectly. ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [March 5, 2024, 10:28am UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/12 "2024-03-05T10:28:29Z")
I think this is a great find. I totally forgot about the anti-virus software. Thank you for posting the solution since it might be useful for other users. ---
**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:** [March 24, 2025, 6:29pm UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/13 "2025-03-24T18:29:34Z")
> [@robertorosa](#): > > After a bit of testing I think my “The mesher is busy” problem has been solved. I had to register the EXE file “NetGen\NetGenMesher.exe” in the DO NOT CHECK list in my antivirus (McAfee). After this operation the import of PrePoMax STEPs works perfectly. I have a new Windows 11 machine with McAfee and now I face the same issue. This solution with McAfee DO NOT CHECK list didn’t work. Interestingly, I have the issue in v2.2.0 and v2.3.0 but not in v2.2.11 dev. What could be the difference ? ![image](https://global.discourse-cdn.com/free1/uploads/prepomax/original/2X/0/07d0520e04df37f94dd1bacb7defa73a2c15036c.png) ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [March 25, 2025, 12:38pm UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/14 "2025-03-25T12:38:35Z")
That is interesting. It seems running netgen is a problem. But the import routine, which calls NetGenMesher.exe, uses the old file created a while ago. So this behavior is unexpected. ---
**Author:** ![JTK](https://avatars.discourse-cdn.com/v4/letter/j/ea5d25/32.png) [@JTK](https://prepomax.discourse.group/u/JTK)\ **Post date:** [July 3, 2025, 7:31am UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/15 "2025-07-03T07:31:31Z")
Hi 🙂 I am new to PreProMax and unfortunately I am facing the same problem: I cannot open stp documents. My file will open as stl but then I cannot transfinite mesh. When I import the same file as stp, no geometry is loaded. I tried several PrePoMax versions and also put the exe in different folders. Can you please help me? I can provide you with the stp data: [https://drive.google.com/file/d/1XW7nvuKs9YXil8ev7Dw3SBd3wBFcEzGk/view?usp=drive\_link](https://drive.google.com/file/d/1XW7nvuKs9YXil8ev7Dw3SBd3wBFcEzGk/view?usp=drive_link) This is very important to me so I am looking forward for help. Thank you! ---
**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:** [July 3, 2025, 7:40am UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/16 "2025-07-03T07:40:36Z")
To share this file, you have to set access to “Anyone with the link” first and then copy the link. But are you able to import other .step files ? ---
**Author:** ![JTK](https://avatars.discourse-cdn.com/v4/letter/j/ea5d25/32.png) [@JTK](https://prepomax.discourse.group/u/JTK)\ **Post date:** [July 3, 2025, 7:53am UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/17 "2025-07-03T07:53:32Z")
I am sorry, here is the new link: [https://drive.google.com/file/d/1XW7nvuKs9YXil8ev7Dw3SBd3wBFcEzGk/view?usp=sharing](https://drive.google.com/file/d/1XW7nvuKs9YXil8ev7Dw3SBd3wBFcEzGk/view?usp=sharing) I tried it with another .stp file and it worked..? But what is wrong with my current file? ---
**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:** [July 3, 2025, 8:02am UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/18 "2025-07-03T08:02:15Z")
I can’t import this .step file either. Even to FreeCAD. It seems to be broken. Maybe export failed for some reason. ---
**Author:** ![JTK](https://avatars.discourse-cdn.com/v4/letter/j/ea5d25/32.png) [@JTK](https://prepomax.discourse.group/u/JTK)\ **Post date:** [July 3, 2025, 8:10am UTC](https://prepomax.discourse.group/t/problems-importing-step-and-stp-files/1452/19 "2025-07-03T08:10:44Z")
Thank you! Now I know where to start for solving this problem.