Wait

wait.ps1

[string]$LockFile = "C:\Test\Lockfile.txt"
[int]$wait = 15 #seconds to wait before checking the content of $lockfile again.

#Creating $lockfile if it doesnt exist
If ((Test-Path $LockFile) -eq $false){
    Write-Output "$lockfile does not exist on $env:computername. Creating it..."
    New-Item $LockFile -ItemType file -Verbose
    "Available" | Out-File $LockFile
}

do{
    $content = Get-Content $LockFile
    if($content -eq "Available"){
        Write-Output "Content of $lockfile is 'Available'. Moving on to next step"
        $continue = $true
    }
    else{
        Write-Output "Content of $lockfile is '$content' Checking again in $wait sec"
        Start-Sleep -Seconds $wait
    }
}while($continue -ne $true)