Error 000819: The tool is not available or is unassigned with update to Pro 2.5

[MollyMoore]

I have a custom Python Toolbox that has been running fine. Since the update to Pro, when I run the script, the program immediately crashes and if I can open the dialog box in time, it contains the following error:

Error 000819: The tool is not available or is unassigned

All of my third party packages are in the python environment that is active in Pro and I have background processing turned off int he script.

I'm not sure what else to try. What would have changed in the update to make this suddenly start to happen?

[DanPatterson_Retired]

What tools are you using?

Did you try the suggestion of importing the toolbox?

000819: The tool is not assigned.—Help | Documentation 

[MollyMoore]

I'm trying to run the custom python toolbox from within Pro. I'm struggling to understand why I need to import the toolbox into the toolbox itself - and thus struggling with how I should try to write this in within the script.

I did create a new toolbox in Pro and copy and pasted my custom toolbox into it and that worked. However, I'd like for the tool to be able to run from a static file location without having to copy/paste into a new toolbox because others will be using it within our organization and it's easier to push out edits like this.

[DanPatterson_Retired]

Did you try to remove the original toolbox and re-add it?  The location may have changed and references to the toolbox's tools will become broken.

Also are you storing the toolbox in a folder or in a gdb?

[MollyMoore · Accepted solution]

Okay, after much trial and error, it seems that a period was the culprit. A period used to designate version number of the tool in the alias and label were breaking the tool after the update to Pro 2.5.

[KoryKramer]

Sorry that you ran into this, Molly Moore‌.  It looks like this was reported to Technical Support as BUG-000128546: ArcGIS Pro crashes if a tool is run in a Python tool.. The development team will look at getting this fixed as soon as possible and, if feasible, I'm sure will try to get in a patch for 2.5.  If interested in following status updates, you can go to that link and click the Subscribe button.

Thank you.