How to solve the screen flickering on a XPS 13 (2015)


I’ve been using a beautiful Dell XPS 13 (9343) for the last 3 months as my primary machine. Not only has it a decent processor (i7), it also has a beautiful high resolution screen. The brightness and contrast is much better than on the Lenovo X1 Carbon that I’ve been using previously. But the screen has also been the source of some headaches…

After installing our corporate Windows 10 Enterprise installation on the XPS, I’ve noticed some annoying flickering of the screen.

It’s not always there, but it seems to be triggered by the power management. When waking up it showed behavior similar to below. (which is not my video)

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The case of the missing IP addresses

In a VMware vSphere 5.5 environment we discovered a strange issue with most VM’s. After a reboot they would lose their network connectivity. It doen’t matter if they run 2008 R2, 2012 or 2012 R2, they all show the same behavior.

  • They are unreachable over the network
  • In vSphere they show the correct IP address
  • When logged in on the console of the machine, it shows an APIPA address next to the fixed IP address
  • Making any change to the VM NIC triggers the VM to use the correct IP again. This includes the ‘connect at power on’ option.

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High resolution user pictures in Office 365

Imagine you have a bunch of pictures of your users… and imagine that they are 648×648 pixels and are named %username%.jpg.

Wouldn’t it be awesome if you could upload those in Office 365 without bothering your users with an instruction?

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Slow client Hyper-V in Technical Preview

I decided my life was too easy. I’ve replaced Windows 8.1 update with Windows 10 Technical Preview on my primary machine. Overall this works pretty well, but I did run into a performance problem with client Hyper-V.

When setting up a demo virtual machine with Windows 8.1 I noticed it was very slow. I use a Gen-1 machine for the legacy nic, I have a MDT installation in place to install machines like this, so it was more out of habbit than anything else.

Since the performance was miserable, I decided to plug in the ISO and use that one. This wasn’t much faster, so I decided to do the same install with a new VM with Gen-2 as a base. This did the trick. As you can see in the screenshot below, the left machine took almost 27 minutes to come to the same point as the right one did in just over 2 minutes.

So whenever possible… use Gen-2 VM’s.



Adding trusted senders to Office 365

One of the strenghts of Sharepoint is imo the user subscribed email alerts.

Our SharePoint admin created a workflow that produces an email. This email contains some HTML to make it pretty.

Outlook however, by default, blocks the HTML and the receivers end up with an email that’s well… ‘not’ so pretty.

Click here to download pictures. To help protect your privacy, Outlook prevented automatic download of some pictures in this message.

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DPM 2012 R2 system state backup fails on Windows 2012 server

Just a quick one. One of our few 2012 non R2 servers gave an error when trying to create a recovery point:


The following alert occurred at 10/7/2014 10:24:03 AM.

The replica of Non VSS Datasource Writer on server.domain.local is inconsistent with the protected data source. All protection activities for this data source will fail until the replica is synchronized with consistency check.DPM failed to create the backup. If you are backing up only System State, verify if there is enough free space on the protected computer to store the System State backup. 
On protected computers running Windows Server2008, verify that Windows Server Backup (WSB) is installed and that it is not performing any other backup or recovery task.

The resolution is mentioned in the last line of the error. Don’t let the Windows Server 2008 fool you, 2008 R2 and 2012 both need the feature installed if you need a System State backup.

For 2012 Server you can simply use the following command:

No reboot is needed.


Enable Lync users automatically with PowerShell

To enable a user for Lync, some admin interaction is normally necessary. To make life a bit easier, but to stay in-control at the same time, I wrote a PowerShell script.

The key features are;

  1. Checks for usersobjects in multiple user defined OUs
  2. Checks if the userobjects are enabled
  3. Checks if the userobject has an emailaddress
  4. Enables the account for Lync
  5. Sends an email to a predefined address whenever users are enabled.

You can find the script in the TechNet Gallery:


If you want to schedule it, simply create a scheduled task which runs;

c:\windows\system32\WindowsPowerShell\v1.0\Powershell.exe -file “c:\pathtops1\Enable-Lync.ps1”


Who says the command line isn’t sexy?

Recently I have been doing a lot with Powershell. There is just one issue… a blue window with white text on it, it’s not really cool is it? Especially when you are running lenghty scripts, it just looks cool for geeks like myself.

How cool would it be if the PowerShell window could be transparant? It doesn’t add any functionality ofcourse, but it does look sexy.

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renewing Exchange 2013 certificate fails

Recently a customer contacted me with an Exchange 2013 issue. Their Exchange certificate was about to expire and they had some trouble renewing the certificate on one of their Client Access servers.

The 3rd party certificate was successfully imported and activated on the 1st CAS server, but it failed to import on the 2nd CAS server.

Trying to import the certificate generated an error; “Cannot import certificate. A certificate with the thumbprint xxx already exists.”
Get-Exchangecertificate -server CAS2 didn’t return a certificate with that thumbprint.

I decided to start MMC and add the Certificates snap-in for the computer account. And there it was, the 3rd party certificate was already there and in the details was the thumbprint that corresponded with the error message.

After deleting the certificate and an iisreset. After reopening the ECP it was possible to import the certificate from the ECP and assign it for the appropriate services.


What I bring when I travel

Next week I’ll be attending TechEd in New Orleans. Since some people ask me what I’ll bring, I thought it maybe would make an interesting blog post.
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