This all has worked fine previously, but latest updates for some reason there have been these kind of issues, as described below.

1. Start Jenkins service
2. Trigger ex. 20 builds
3. Wait and see if one of them fails to build
4. See if the reason is Jenkins issue, not msbuild/unit test
5. Rest of builds that starts after failed one, will fail also with same output as below
6. Wipe workspaces manually
7. Builds will most likely start working again

Triggered by Gerrit: http://xxx002:8080/4195
[EnvInject] - Loading node environment variables.
Building on master in workspace r:\jenkins-workspaces
Fetching changes from the remote Git repository
Fetching upstream changes from ssh://hudson@xxxx002:29418/xxx.git
Checking out Revision 45d62ed078309607e0b6a24b842ff33c93f3b740 (feature/WI3076)
Cleaning workspace
Resetting working tree
FATAL: Command "git clean -fdx" returned status code 1:
stdout: Removing Source/xxx/zzz/Areas
Removing Source/xxx/zzz/Content
Removing Source/xxx/zzz/Scripts
Removing Source/xxx/zzz/Views

stderr: warning: failed to remove Source/xxx/zzz/Areas
warning: failed to remove Source/xxx/zzz/Content
warning: failed to remove Source/xxx/zzz/Scripts
warning: failed to remove Source/xxx/zzz/Views

hudson.plugins.git.GitException: Command "git clean -fdx" returned status code 1:
stdout: Removing Source/xxx/zzz/Areas
Removing Source/xxx/zzz/Content
Removing Source/xxx/zzz/Scripts
Removing Source/xxx/zzz/Views

stderr: warning: failed to remove Source/xxx/zzz/Areas
warning: failed to remove Source/xxx/zzz/Content
warning: failed to remove Source/xxx/zzz/Scripts
warning: failed to remove Source/xxx/zzz/Views

at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandIn(CliGitAPIImpl.java:1086)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandIn(CliGitAPIImpl.java:1063)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommand(CliGitAPIImpl.java:900)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommand(CliGitAPIImpl.java:910)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.clean(CliGitAPIImpl.java:367)
at hudson.plugins.git.GitAPI.clean(GitAPI.java:251)
at hudson.plugins.git.extensions.impl.CleanCheckout.onCheckoutCompleted(CleanCheckout.java:28)
at hudson.plugins.git.GitSCM.checkout(GitSCM.java:890)
at hudson.model.AbstractProject.checkout(AbstractProject.java:1415)
at hudson.model.AbstractBuild$AbstractBuildExecution.defaultCheckout(AbstractBuild.java:652)
at jenkins.scm.SCMCheckoutStrategy.checkout(SCMCheckoutStrategy.java:88)
at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:561)
at hudson.model.Run.execute(Run.java:1678)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:231)