Microsoft DevOps Testing Agent "Cannot publish artifacts from OSX or Linux" - azure-devops

Question

I am running a local Microsoft DevOps server along with two separate machines running test agents for nightly automated testing. I recently configured a third test agent, but have run into issues with it publishing artifacts during the Build jobs to be used by the Release jobs.
The same jobs run perfectly on the two existing test boxes, but always throw this error after the build has completed and during the artifact publishing step:
2020-09-01T21:32:29.2544245Z ##[section]Starting: Publish Artifact:
bin_drop 2020-09-01T21:32:29.2548130Z
============================================================================== 2020-09-01T21:32:29.2548196Z Task : Copy and Publish Build
Artifacts 2020-09-01T21:32:29.2548235Z Description : [DEPRECATED] Use
the Copy Files task and the Publish Build Artifacts task instead
2020-09-01T21:32:29.2548273Z Version : 1.0.32
2020-09-01T21:32:29.2548311Z Author : Microsoft Corporation
2020-09-01T21:32:29.2548365Z Help : More
Information
2020-09-01T21:32:29.2548404Z
============================================================================== 2020-09-01T21:32:30.7956739Z ***.runsettings
2020-09-01T21:32:30.8306609Z ##[error]Cannot publish artifacts from
OSX or Linux to a file share. You can change 'Artifact Type' to
'Server', use Windows, or use the 'Copy Files', 'Copy Files Over SSH',
or 'FTP Upload' task. 2020-09-01T21:32:30.8378696Z
##[section]Finishing: Publish Artifact: bin_drop
In attempting to solve this issue I did look into using the Publish Build Artifacts task instead, but its description says it would have the same problem (e.g. doesn't work on Linux etc.). To be clear, the newest test box is the same as the other two running windows 10, it is NOT running linux or OSX.
In looking at Microsoft's test agent code (I think I found the correct GitHub package here), it looks like they are using Node.js to detect the platform the agent is running on, and if it does not equal 'win32', then they are throwing this error.
So I navigated to the Node.js instance inside the agent:
\agent\externals\node\bin
\agent\externals\node10\bin
and ran this code, and verified that it did indeed return 'win32' from both Node.js instances:
const os = require('os');
console.log(os.platform());
As near as I can tell the configuration on the third box is the same as the other two Windows 10 test boxes. And this should not be throwing this error. Does anyone have an idea why the test agent might be getting a value other than 'win32' so it thinks it is not running on windows and throwing this error for me?
EDIT:
I did try removing and re-configuring the agent on the machine. On all the text boxes the agent is running in interactive mode so it can run GUI tests.
Also, I recently had to rebuild one of the other two test boxes (after I was already struggling with box 3), and that rebuild went fine. A complete re-install of everything and it is working perfectly just like it was before.

Answer 1

I was able to solve this issue by copying the agent from a working test machine. It seems as though the more recent agent downloaded from the DevOps server itself has a bug in it.
Copying the agent from a working machine and stripping all the _work and configuration data from it, then installing it on the new third test machine resulted in a working machine.
The test machine I rebuilt while struggling with machine three was successful because I did not do a full reformat. Just reinstalled the OS, then used the install files from its data drive to finish installing the required software on it, so I never had to download a new agent for it from the DevOps server.