Virtual-environments: nuget restore started failing on windows-2019 20200531.1

[mcooley]

Describe the bug
"nuget restore" started encountering the following error in our environment: "NuGet.CommandLine.CommandLineException: MsBuild timeout out while trying to get project to project references."

The pipeline runs successfully with image version 20200524.1:
https://dev.azure.com/ms/calculator/_build/results?buildId=85001&view=logs&j=27ae15c2-a210-5a44-c856-4adc1d2b6ec9&t=023355e4-6a4e-54d0-4c0e-f65a98cfc541

But it fails with image version 20200531.1:
https://dev.azure.com/ms/calculator/_build/results?buildId=85241&view=logs&j=27ae15c2-a210-5a44-c856-4adc1d2b6ec9&t=023355e4-6a4e-54d0-4c0e-f65a98cfc541

Area for Triage:
Packages

Question, Bug, or Feature?:
Bug

Virtual environments affected

• [ ] macOS 10.15
• [ ] Ubuntu 16.04 LTS
• [ ] Ubuntu 18.04 LTS
• [ ] Ubuntu 20.04 LTS
• [ ] Windows Server 2016 R2
• [X] Windows Server 2019

Note
I confirmed that:

• Updating to a newer version of NuGet.exe does not fix the problem
• Using NuGet.exe to restore the solution works successfully locally

Expected behavior
"nuget restore" runs successfully

Actual behavior
See links to the pipeline failure above. (The repo and pipeline definitions are open source.)

[maxim-lobanov]

Hello, thank you for your report.
I see that the latest your build is green. Could you please try to rerun pipeline a few more times to confirm that it was not temporary network issue?

[mcooley]

It appears that the builds are passing today. This is weird because the step that's failing doesn't indicate it's making a network request in any way, but I am happy the issue is resolved.

[maxim-lobanov]

Great, Please let us know if you see the same issue again