Failed to Load System Tools ArcGIS Pro 2.5

[NatalieRobbins]

When upgrading to ArcGIS Pro 2.5, I get the attached error: Failed to load system tools. I have tried renaming the C:/Users/<user profile>/AppData/Roaming and C:/Users/<user profile>/AppData/Local folders to ESRI_Old as suggested on other threads and have totally uninstalled and reinstalled AGP on the computer. Suggestions??

Edited to say that conda method from the following help article also did not remedy the issue: Problem: After upgrading to ArcGIS Pro 2.2, geoprocessing tools fail to load and Python window retur... 

[NatalieRobbins]

As an update to this, the issue was caused by the ENVI Analytic python toolbox and was remedied by deleting out the pyt that was causing the issue.

[WilliamMayr]

I am having this same issue but it lists different files. Renaming the file did not fix the issue but just show a different file. We need some help on this one...

C:\Program Files\ArcGIS\Pro\Resources\ArcToolBox\Toolboxes\Intelligence Tools.pyt

[NatalieRobbins]

I will tell you what worked for me. I went to C:\Program Files\ArcGIS\Pro\Resources\ArcToolBox\Toolboxes and then just deleted the problematic toolbox. I think the issue is that whatever toolbox has a space in its name. 

[Roxana_ElenaUrdea]

Hi, 

I reccomend to uninstall the application, delete all the content folder: C:\Program Files\ArcGIS\Pro and install again 2.5 version.

[DrewFlater]

There are multiple things going on here.

Natalie Robbins‌ correctly identified she had a custom Python toolbox in the system toolbox directory, and that ENVI toolbox likely didn't have the correct libraries to work with the updated ArcGIS Pro 2.5 Python environment. Installing 3rd party toolboxes into your system toolbox directory can have these negative effects when moving between Pro versions. 

William Mayr‌ had you previously cloned and made a custom Python environment? Environments need to be repaired or re-cloned when updating versions of ArcGIS Pro. The Intelligence Tools PYT toolbox is not the problem, that just happens to be the first Python functionality that the application is trying to load, as the system loads all the system toolboxes alphabetically (that is alphabetically the first toolbox in the system toolbox directory built with Python). Removing that PYT will just make the next one in the system toolbox directory fail. You have an underlying Python environment problem that must be remedied to proceed. You may want to contact tech support if none of this Python environment stuff that I mentioned applies to you

[JackSilburn]

Hi Drew

I am having similar issues to the above user(s). See my comments/troubleshooting here.

Are you able to explain further about the Python environment issue you mentioned above. I believe I am in much the same situation.

Regards