MSBulid ItemGroup stopped working when ** included - msbuild

Question

I have an existing msbuild script that's been working for a long time and it WAS working today, but all of a sudden my ItemGroup that searches for files recursively is no longer getting translated. I simplified the script below which still doesn't work:
<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="15.0" DefaultTargets="Main" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
<Target Name="Main">
<ItemGroup>
<CsProjFilesLoad Include="C:\Temp\**\*.csproj" />
</ItemGroup>
<Message Text="CsProjFilesLoad: #(CsProjFilesLoad)" />
</Target>
</Project>
This is what gets printed
**********************************************************************
** Visual Studio 2017 Developer Command Prompt v15.9.19
** Copyright (c) 2017 Microsoft Corporation
**********************************************************************
C:\Temp>msbuild "Build.xml" /t:Main
Microsoft (R) Build Engine version 15.9.21+g9802d43bc3 for .NET Framework
Copyright (C) Microsoft Corporation. All rights reserved.
Build started 02/08/2020 07:51:51 AM.
Project "C:\Temp\Build.xml" on node 1 (Main target(s)).
Main:
CsProjFilesLoad: C:\Temp\**\*.csproj
Done Building Project "C:\Temp\Build.xml" (Main target(s)).
Build succeeded.
0 Warning(s)
0 Error(s)
Time Elapsed 00:00:01.35
I'm very confused at why the ItemGroup is no longer returning me a semi-colon list of the csproj files. Can anyone provide any insight? I rebooted my machine in case some environment thing went wacky but still no luck. I can run the same script on another machine and it works perfectly fine like this:
C:\Temp>msbuild "Build.xml" /t:Main
Microsoft (R) Build Engine version 12.0.40629.0
[Microsoft .NET Framework, version 4.0.30319.42000]
Copyright (C) Microsoft Corporation. All rights reserved.
Build started 2/8/2020 8:04:12 AM.
Project "C:\Temp\Build.xml" on node 1 (Main target(s)).
Main:
CsProjFilesLoad: C:\Temp\Sample\Sample.csproj
Done Building Project "C:\Temp\Build.xml" (Main target(s)).
Build succeeded.
0 Warning(s)
0 Error(s)
Time Elapsed 00:00:00.04
so obviously some weird thing has occurred on my machine. Any advice would be much appreciated.

Answer 1

It turns out one of the directories in my file structure was locked/couldn't be accessed and instead of msbuild displaying an error it just didn't translate to what it could access.
What caused this was I deleted my workspace from Azure, deleted all the files in that folder structure but one of the .vs folders didn't delete as it was in use by Visual Studio, I ignored that and recreated the same workspace without deleting that .vs folder. That's when I started encountering the error. Just for grins I deleted the workspace again, closed visual studio, deleted the entire folder structure and re-downloaded everything from source control and that resolved the issue.