I cannot open the Rhino3d File saying "3dm is not rhino m archive file"

I’m using the Educational Version of Rhino 7. I save that file in my external drive - SSD.

I used “Rescue3dmfile” command and analyzed it, it says

"To find damaged parts of the file, search for the word “ERROR” in the following list.

====== FILENAME: D:\Thesis\모델링\Physical Model_2.3dm
ERROR Read3dmStartSection() failed"

Please help me out as soon as possible this is for my spring graduation exhibition project.

Thank you for your help guys
화면 캡처 2023-05-12 082600
화면 캡처 2023-05-12 082620

I looked into this file with tex editor and I found that there is no a kind of section saying this is a 3d geometry file - like below. The below one is from another file that runs well without any error.

My file was definitely Rhino file and I don’t know why it was changed into not Rhino ones…?

“3D Geometry File Format 70 ? Rhinoceros 7.28 - 援먯쑁 ?ㅼ뒿?ㅼ슜 ?쇱씠?쇱뒪, build 2023-02-27 - (compiled Feb 27 2023)
SDK Version: 2348836105.2389738701
OpenNURBS Version: 2389738701
3dm Version: 7
Operating System: Windows 11 (10.0.22621 SR0.0) or greater, 64-bit, platform 2, version 10.0 build 22621 sp 0.0, suite 768, product type 1
Runtime: ON::RuntimeEnvironment::Windows 3DM I/O processor: OpenNURBS toolkit version 2389738701 (compiled on Feb 27 2023)”

Your best option is to go to your Windows Recycle Bin, find the most recent version of the file, restore it, then rename it back into your Documents folder.
You may have to remodel the most recent changes.
I’m afraid there is no hope for the damaged file.

1 Like

Hi everyone
I’m facing the same issue, i have never saved my files in local disk.
i have all my files saved in my google drive but unfortunately
I’m unable to recover this file
using Rhino 8
please suggest me way to open this file


24ft chajja.3dm (9.1 MB)

Hi Hari -

I’m afraid that Audit3dmFile gives me the following:

Testing 3dm Archive: C:[…]\Hari Killada - 24ft chajja.3dm
ERROR - Unable to read start section.
If this was a 3dm file, it is has been corrupted and can no longer be read.

Running Rescue3dmFile and picking the List option shows that there are no recoverable objects in that file.

As John wrote, your best option is to check the Windows Recycle Bin and find the last autosave version of that file.