Best to report to the PyRevit forum as Dynamo can’t really do anything about this one.
You can try disabling all other Revit add-ins and Dynamo customizations to see if that fixes things though.
Okay Thanks
Try following this video for the installation by Erik, might help in the resolution.
Regards,
BM
For anyone else coming across this topic, pyrevit is still work in progress for Revit 2025, and I can attest there have been many issues with compatibility to pre-2025 versions as well as general loading/clashes with addins during this process. I suspect we will see a stable build just before Revit 2026 lands, then another delay to support that, and so on, so forth. They are relying on community support and it is slow going.
In the context of Dynamo, my understanding is pyRevit currently has lots of issues running Dynamo scripts, and the development team does not see this as a high priority item to fix versus supporting pyRevit libraries and Python support initially. Nonica toolbar or Relay are great alternatives if your goal is to run Dynamo scripts in a toolbar.
Do let them know via their github as an issue, or on the forums (but github is better).
The challenges we see here are a testament to the work the Dynamo team themselves have done to make sure we had a 2025 Dynamo ready to go in April this year.