Powershell Invoke-Command 在手动运行时有效，但在脚本中无效

我正在构建一个脚本来远程安装 PSWindowsUpdate PowerShell 模块，打开正确的防火墙端口，然后运行命令来安装等待更新。为了安装 PSWindowsUpdate 模块，我需要在我的一些机器上安装 MSI 以启用“Install-Module”命令行开关。

如果我在本地计算机上的管理员 PowerShell 会话中手动运行以下代码，它可以正常工作：

$RemoteMachine = "DCSvrRDS16"
write-host "Server Name is: $RemoteMachine"

#Copy the MSI Local to the computer
Write-Host "Copying MSI locally"
Copy "\\dcsvrstorage2\software\microsoft\powershell\PackageManagement_x64.msi" \\$RemoteMachine\c$\

#Run the MSI remotely
Write-Host "Running MSI"
Invoke-Command -ComputerName $RemoteMachine -Credential $domaincredentials -ScriptBlock { c:\windows\system32\msiexec /i c:\PackageManagement_x64.msi /quiet /lvx* c:\PackageManagement.log } 4>&1

但是，如果我在完全相同的已打开 PowerShell 会话中运行此完整脚本，则不会安装 MSI 并且不会创建日志文件：

Import-Module PSWindowsUpdate
$domaincredentials = Get-Credential


Function ProcessMachine($RemoteMachine) {

    write-host "Server Name is: $RemoteMachine"

    #Copy the MSI Local to the computer
    Write-Host "Copying MSI locally"
    Copy "\\dcsvrstorage2\software\microsoft\powershell\PackageManagement_x64.msi" \\$RemoteMachine\c$\

    #Run the MSI remotely
    Write-Host "Running MSI"
    Invoke-Command -ComputerName $RemoteMachine -Credential $domaincredentials -ScriptBlock { c:\windows\system32\msiexec /i c:\PackageManagement_x64.msi /quiet /lvx* c:\PackageManagement.log } 4>&1

    #Install the module
    Invoke-Command -ComputerName $RemoteMachine -Credential $domaincredentials -ScriptBlock { Install-Module PSWindowsUpdate -Force }

    #Turn on the firewall rules
    Invoke-Command -ComputerName $RemoteMachine -Credential $domaincredentials -ScriptBlock { Set-NetFirewallRule -DisplayName "COM+ Network Access (DCOM-In)" -Enabled True }
    Invoke-Command -ComputerName $RemoteMachine -Credential $domaincredentials -ScriptBlock { Set-NetFirewallRule -DisplayName "COM+ Remote Administration (DCOM-In)" -Enabled True }
    Invoke-Command -ComputerName $RemoteMachine -Credential $domaincredentials -ScriptBlock { Remove-NetFirewallRule -DisplayName "Remote WSUS Install" }
    Invoke-Command -ComputerName $RemoteMachine -Credential $domaincredentials -ScriptBlock { New-NetFirewallRule -DisplayName "Remote WSUS Install" -Profile Domain -Enabled True -Direction Inbound -Action Allow -Protocol TCP -LocalPort RPC }

    #Try the update
    Install-WindowsUpdate -ComputerName $RemoteMachine -AcceptAll
}

foreach ($machine in (Get-Content NeedsWSUS.txt)) {

    ProcessMachine $machine

}

这让我快疯了。我已经在远程机器上运行了 ProcessMonitor，我可以看到 msiexec 启动然后停止，而无需访问 C: 驱动器根目录中的 MSI 或尝试打开日志文件进行写入。

有没有人见过类似的东西？客户端机器是 Windows 7 pro、Powershell 4，目标机器是 Windows 2012 R2 和 PowerShell 4。

提前致谢。