Inventor 2025.3 will not open 2026 files

[michaelHR9KR]

I need to use the inventor addin for pronest. the functionality of this broke with Inventor 2026. We already upgraded to 2026. We should have tested the addin. I thought we could work around it by using inventor 2025.3 with pronest but it does not seem to actually open 2026 files as I understood was advertised. Any suggestions?

[johnsonshiue]

Hi Michael,

Prior releases of Inventor cannot "open" files saved in later releases. The workflow you are talking about is like treating Inventor 2026 iam or ipt file as a file from another CAD system. You may "derive" it into Inventor 2025.3.

Another thing to look at is to make sure Inventor Interoperability 2025 has been installed at "C:\Program Files\Common Files\Autodesk Shared\." This component is installed on demand. Or you may install it manually from manage.autodesk.com.

Many thanks!

[SharkDesign]

Hi, what Johnson is referring to is, you will get a 'dumb solid' rather than a full feature browser history.

So if you 'open' a 2026 file with 2025, it runs a translation of the geometry. I don't know how pronest works, but if it's trying to open the file it won't be able to directly without you converting it first to a 2025 ipt. 

[michaelHR9KR]

Thank you. I understand what is being said here. Yes pronest needs actual
information from the model so a dumb solid will not work. this is
disappointing, but that's the way it is sometimes. Next time we will test
all scenarios before updating!