Sluggish performance within Windows 7/10 VDI session (Non network related!)

I’ve come across this now with multiple customers. Most of the time it’s showing up when people are moving to windows 10, after experiencing poor performance with W7 desktop VMs and as part of the migration process, they buy all new tin.

They experience sluggish responses when opening various apps and for example with IE, it’s painfully obvious that something is wrong. It will spike the CPU to a high percentage, take quite a while to open, then the CPU will drop and it’ll be OK for browsing until more tabs are opened and similar behaviour will occur.

When this occurs, I always ask if there’s any resource pools set, any QoS or similar on the storage and so on, but generally, I know there isn’t. vSphere monitoring will show that everything is OK, so will anywhere you look within Horizon and vROPs. I’ll ask if the physical hardware has power management/saving on within the BIOS and I usually get the following answers:

“Oh, I’m sure it’s been turned off, but I didn’t build the servers”

“Yep, no power management, vSphere says so.”

“I don’t know. How do you even do that?”

“I’ve asked and they say it has been.”

Every time. Every. Time. 

It can be difficult to definitely show that this is the source of the problem when everything you have access to says it all should be OK, plus people also have many different levels of experience with these things. I came across it about 7 years ago when the company I worked for had a mix of Dell and HP servers and being a PC gaming enthusiast, I was always trying to eke out as much performance of a PC as I could, so I tried to do the same with servers – no overclocking though! So power saving settings would be the first thing to get turned off!

So if you’re experience similar problems, with apps spiking the CPU, being sluggish, then the CPU dropping, check your physical hardware to make sure power management isn’t set to power saving, it’ll save you a whole load of heart ache! This also applies to Citrix as well.

If you need proof of this, or want to check it, there’s various tools, but I always check using Systrack – we have a tool as part of the suite called Resolve, which allows for in-depth analysis of specific machines (as well as the ability to compare to other machines/groups) and this will show straight away if a machine is being throttled, or has memory ballooning. Throttling can also show if a CPU is overheating and the BIOS throttles it back to avoid shutting down – many a place have thought they need new machines, or new CPUs, but no, they simply need to get those dusty fans cleaned out!


May show up a little bit too small for some screens, but what you’d see, is the CPU is throttled to 66%. The CPU usage is low, but due to the throttling, the Thread count and interrupt per seconds are high. The CPU should be 100% or even higher with some modern CPUs, but unless you’re really trying to save some power… You don’t want it lower than 100%

What’s also interesting, is when people go back to the older servers with Windows 7 on and realise that the poor performance throughout, was also due to the power management not being turned off… as a fair few manufacturers ship hardware with this as default…

Windows update KB3177467 – Causing crashing and boot loop

Oh those were the days. MS updates smashing their way into your infrastructure, leaving Exchange a gibbering wreck, W7 desktops not booting, WSUS not wanting to remove the updates… So glad those days are…gone… Oh wait, no, still happening!

In a physical environment, an update causing an issue with a desktop is a pain the backside – you have multiple options and ways to mitigate this. In a VDI environment… Well, you can imagine the carnage (Like Carmageddon without cars? Desktopgeddon? VDIGeddon? Ok, I’ll stop now.)

After trying multiple solutions, finally stumbled on someone else who had the problem way back in October 2016 and got it sorted out:

Update KB3177467 causing boot loop

Horizon View Client Install – Windows

And now for something completely different.

I mean, now for the Horizon View Windows Install!

Download the Horizon View Client from the following site:


Now, you may not want USB redirection (or it may not work) and also it’s environment dependent whether you want to Log in as current user.


Enter your Default connection server


Continuing on from if you chose to log in as current user


Run the app, log in and go forth!

WannaCry Attack and Petya

Yes, yes, we’re all sick of hearing about it this, but for those of you who didn’t get exposed to it, or did and needed that little bit more information, I’m posting it anyway.

As you may know, it wasn’t just Windows XP machines that got hit (contrary to popular media belief), there was a huge effect on Windows 7 machines that hadn’t been updated in a while.

I worked on this for the NHS and although it was mitigated by being a Horizon View environment, for another Trust, it was absolutely devastating to their physical environment.

So, aside from the patching you’ve all done and the MS KB:

KB4012212 for Win7 and KB4012213 for Server 2012

There is also the option to completely disable SMB v1. You can…Honest… It won’t break anything!

Good article from MS on why you NEED to stop using it and one on how to disable it:

Also, for those of you who would like to use a script, I found the following (somewhere!) Credit to the author!





# Disable SMB V1 – Windows Server 2012 R2, Windows 10 and Windows 8.1

$ComputersList = Get-Content -Path “D:\temp\testservers.txt”

Invoke-Command -ComputerName $ComputersList {Remove-WindowsFeature FS-SMB1 -NoRestart}


# Disable SMB V1 – Windows 8 and Windows Server 2012

$ComputersList = Get-Content -Path “D:\temp\testservers.txt”

Invoke-Command -ComputerName $ComputersList {Set-SmbServerConfiguration -EnableSMB1Protocol $false}


# Disable SMB V1 – Windows Server 2008, Windows Server R2, Windows 7 and Windows Vista

$ComputersList = Get-Content -Path “D:\temp\testservers.txt”

Invoke-Command -ComputerName $ComputersList {Set-ItemProperty -Path”HKLM:\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters” SMB1 -Type DWORD -Value 0 -Force}







# Disable SMB V1 – Windows Server 2012 R2, Windows 10 and Windows 8.1

$ComputersList = Get-Content -Path “D:\temp\testservers.txt”

Invoke-Command -ComputerName $ComputersList {Disable-WindowsOptionalFeature -Online -FeatureName smb1protocol -NoRestart}


# Disable SMB V1 – Windows Vista, Windows Server 2008, Windows 7, Windows Server 2008 R2, Windows 8, and Windows Server 2012

$ComputersList = Get-Content -Path “D:\temp\testservers.txt”

Invoke-Command -ComputerName $ComputersList {sc.exe configlanmanworkstation depend= bowser/mrxsmb20/nsi}

Invoke-Command -ComputerName $ComputersList {sc.exe config mrxsmb10start= disabled}


Just goes to show that the reluctance for various institutions to perform updates needs to be overcome, as the consequences for older OS are becoming more and more serious!