API uploaded .step file cannot be opened but locally uploaded .step file can because of mismatch in version.

[r_vanderheijdenR5T8S]

I'm uploading .STEP files with the API from a web interface. When I try to open them locally using my Autodesk Fusion Client, I get this error:

Fusion can't open 4022.645.71281_AB-01.step v1, which was persisted by version 2701.0.7 with your current software version 2605.1.52.

However, I've downloaded the latest version of Fusion and can't download a newer version. I can't open the .STEP files. But when I upload the same file locally with the Fusion Client is does convert the .STEP correctly to .f3d and I'm able to work with it perfectly.

It looks like a mismatch of versions when uploading with the API vs Locally.

This was working on 14 January 2026 and broke on 15 January 2026.

[BrianEkins]

What exactly are you using to upload the files?

The version referenced in the error is being released next week, or is available now to Fusion Insiders. I don't know if someone updated the backend too early or if the interface you're using is a pre-production API and this is expected.

[r_vanderheijdenR5T8S]

Hello Brian,
I used this guide to upload files to the Fusion Cloud: https://aps.autodesk.com/en/docs/data/v2/tutorials/upload-file/

To be more precise I build an web application with HTML, CSS and Javascript. Here I use javascript fetch requests to upload the files to the cloud. I do that in the order of the tutorial.

[r_vanderheijdenR5T8S]

Hello Brian,

It seems like someone updated the backend to early again. It's on version 2701.0.7 but the latest normal Fusion version is on: 2606.1.22

I didn't want to open a new thread because of it's the same issue I'm having.

If there is any extra information you need, feel free to ask.