Since Windows 8.1 reached GA today, I loaded it up first thing this morning on my Ativ Book 7 to enjoy the much anticipated tweaks that make this Ultrabook even more ultra! However, once I got the update installed, I opened a few applications, including Chrome, and a XenDesktop 7 ICA session using Receiver for Windows and immediately noticed that these apps were blurrier than the desktop or Modern Apps.

As you can see in this screen clip, there’s a slight blur on the seamless ICA desktop (110%ish scaled), as is the CDViewer taskbar icon:

I quickly found that Microsoft decided to enable dynamic display scaling on non DPI Aware programs for high-DPI displays. If you’re interested (like I was) to know more about why Microsoft made this decision in 8.1, you should check out this blog which goes into detail on the topic.

The short of it is that the ‘..additional scaling capability provides two distinct advantages for high-DPI displays on Windows 8.1:

1. UI can scale larger which makes readability better and touch/mouse interactions easier.
2. 200% scaling enables pixel-doubling for up-scaling which provides a clear and crisp appearance for images, graphics, and text.

Since the Ativ 7 crams a 1080p display into a 13.3″ panel, it falls under the category of a high DPI display at about 165 PPI. To change this behavior for a particular application, you have to adjust the executable’s compatibility settings to ‘Disable display scaling on high DPI settings’:

Disable display scaling on high DPI settings

By doing this for CDViewer.exe, for example, I was able to get the ‘Desktop Viewer’ to launch in native DPI, which is blur free (and displayed in normal DPI). If I need to get a more readable/usable DPI, I can always adjust the same settings on the virtual desktop side:

This setting can be also be disabled via the registry by setting an AppCompatFlags\Layers Reg_SZ value named as the executable in question, with the string set to HIGHDPIAWARE (in HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\Layers):

You can also disable DPI scaling for all applications on a particular display by checking the ‘Let me choose one scaling level for all my displays’ in the ‘Display’ control panel item, and setting the scaling ratio to 100% (Smaller):

The only caveat to this approach is that DPI scaling is also disabled for Explorer, so the taskbar and desktop will be small as well.

Thanks for the thought Microsoft, but please give us an option to do without this feature!

For those of you out there who are delivering XenApp/XenDesktop through StoreFront, you should definitely make sure to update your Receiver for Windows 4 clients to the latest 4.0.1 hotfix. While this update only contains one fix, it solves a very visible, miserable, and annoying problem.

If you’ve ever connected to a StoreFront Store via Receiver 4.0 through a remote site, you’ve probably seen this window pop up every 10 minutes or so:

Receiver 4.0.1 addresses this very annoying behavior by only prompting for credentials after the expiration timeout period if and when a resource is launched through Receiver.

I’m sure many of you already knew about this fix, but I thought I’d help to spread the word in hopes of sparing others from this frustration on Receiver 4.0 RTM.

I was working on a PVS deployment recently and needed to quickly add some RAM to ~200 PVS streamed VMs. To automate this task, I put together the following PoSH script that combines PowerCLI and the XenDesktop PoSH SDK to add RAM to all machines in a particular desktop group:

###################################################################
#
# Change-VM_Memory_CPU_Count.ps1
#
# -MemoryMB the amount of Memory you want 
#  to add or remove from the VM in MB
# -MemoryOption Add/Remove
# -CPUCount the amount of vCPU's you want 
#  to add or remove from the VM
# -CPUOption Add/Remove
# -DesktopGroup the XenDesktop Desktop Group to run against
# -AdminAddress host name of the XenDesktop DDC to run against
#
# Example:
# .\Change-VM_Memory_CPU_Count.ps1 -vCenter vmvcatl05 -MemoryMB 1024 -MemoryOption Add -DesktopGroup 'All User Windows 7' -AdminAddress CTXXDATL01
#

#
####################################################################

param(
    [parameter(Mandatory = $true)]
    [string[]]$vCenter,
    [int]$MemoryMB,
    [string]$MemoryOption,
    [int]$CPUCount,
    [string]$CPUOption,
	[string]$DesktopGroup,
	[string]$AdminAddress
)    

function PowerOff-VM{
    param([string] $vm)

    Shutdown-VMGuest -VM (Get-VM $vm) -Confirm:$false | Out-Null
    Write-Host "Shutdown $vm"
    do {
        $status = (get-VM $vm).PowerState
    }until($status -eq "PoweredOff")
    return "OK"
}

function PowerOn-VM{
    param( [string] $vm)

    if($vm -eq ""){    Write-Host "Please enter a valild VM name"}

    if((Get-VM $vm).powerstate -eq "PoweredOn"){
        Write-Host "$vm is already powered on"}

    else{
        Start-VM -VM (Get-VM $vm) -Confirm:$false | Out-Null
        Write-Host "Starting $vm"
        do {
            $status = (Get-vm $vm | Get-View).Guest.ToolsRunningStatus
        }until($status -eq "guestToolsRunning")
        return "OK"
    }
}

function Change-VMMemory{
    param([string]$vmName, [int]$MemoryMB, [string]$Option)
    if($vmName -eq ""){
        Write-Host "Please enter a VM Name"
        return
    }
    if($MemoryMB -eq ""){
        Write-Host "Please enter an amount of Memory in MB"
        return
    }
    if($Option -eq ""){
        Write-Host "Please enter an option to add or remove memory"
        return
    }	
    $vm = Get-VM $vmName    
    $CurMemoryMB = ($vm).MemoryMB

    if($vm.Powerstate -eq "PoweredOn"){
        Write-Host "The VM must be Powered Off to continue"
        return
    }

    if($Option -eq "Add"){
        $NewMemoryMB = $CurMemoryMB + $MemoryMB
    }
    elseif($Option -eq "Remove"){
        if($MemoryMB -ge $CurMemoryMB){
            Write-Host "The amount of memory entered is greater or equal than 
            the current amount of memory allocated to this VM"
            return
        }
        $NewMemoryMB = $CurMemoryMB - $MemoryMB
    }

    $vm | Set-VM -MemoryMB $NewMemoryMB -Confirm:$false
    Write-Host "The new configured amount of memory is"(Get-VM $VM).MemoryMB
}

function Change-VMCPUCount{
    param([string]$vmName, [int]$NumCPU, [string]$Option)
    if($vmName -eq ""){
        Write-Host "Please enter a VM Name"
        return
    }
    if($NumCPU -eq ""){
        Write-Host "Please enter the number of vCPU's you want to add"
        return
    }
    if($Option -eq ""){
        Write-Host "Please enter an option to add or remove vCPU"
        return
    }

    $vm = Get-VM $vmName    
    $CurCPUCount = ($vm).NumCPU

    if($vm.Powerstate -eq "PoweredOn"){
        Write-Host "The VM must be Powered Off to continue"
        return
    }

    if($Option -eq "Add"){
        $NewvCPUCount = $CurCPUCount + $NumCPU
    }
    elseif($Option -eq "Remove"){
        if($NumCPU -ge $CurCPUCount){
            Write-Host "The number of vCPU's entered is higher or equal 
            than the current number of vCPU's allocated to this VM"
            return
        }
        $NewvCPUCount = $CurCPUCount - $NumCPU
    }

    $vm | Set-VM -NumCPU $NewvCPUCount -Confirm:$false
    Write-Host "The new configured number of vCPU's is"(Get-VM $VM).NumCPU
}

#######################################################################################
# Main script
#######################################################################################

$VIServer = Connect-VIServer $vCenter
If ($VIServer.IsConnected -ne $true){
    Write-Host "error connecting to $vCenter" -ForegroundColor Red
    exit
}

if($MemoryMB -or $CPUCount -ne "0"){
    foreach ($vm in get-brokerdesktop -DesktopGroupName $DesktopGroup -AdminAddress $AdminAddress -PowerState Off)
	{	
		$vmwvm = Get-VM -Name $vm.HostedMachineName
		if ($vmwvm.MemoryMB -lt 4000)
		{
        	if($MemoryMB -ne "0"){
	            if($MemoryOption -eq " ") {Write-Host "Please enter an option to add or remove memory"}
	            else
				{					
	                Change-VMMemory $vm.HostedMachineName $MemoryMB $MemoryOption					
	        	}    
			}
        }

        if($CPUCount -ne "0"){
            if($CPUOption -eq " ") {Write-Host "Please enter an option to add or remove cpu"}
            else{
                Change-VMCPUCount $vmName $CPUCount $CPUOption
            }
        }

    }
}

Disconnect-VIServer -Confirm:$false