Mar 14

Your devices may not receive any Windows security updates as of January 2018

UPDATE: March patches relax antivirus restrictions.

If you’ve not been offered any security updates since January there’s a reason. It appears that some Antivirus programs make unsupported API calls to Windows kernel memory that interfere with January’s updates (especially Meltdown and Spectre patches) and may lead to BSoDs (Blue Screen of Death). To protect customers Microsoft have stopped offering security updates to devices with unsupported AVs.

While waiting for a fix from AV vendors (and if you’re absolutely sure you know what you’re doing) you can temporarily disable the compatibility check. The fix is just a registry key:

According to Microsoft as of March 13-th most of the AV vendors have fixed their products so the compatibility check will be removed soon.

You can find more information here:

Feb 12

PowerShell™ Notes for Professionals & other books

Stack Overflow used to run an interesting project – Stack Overflow Documentation. It is currently shut down, but thanks to it we now have interesting free books like “PowerShell™ Notes for Professionals book“:

Please keep in mind it was created by SO content that may not be very accurate, like what I’d recently discovered:Are the cmdlets in a pipeline executing in parallel?

Anyway I’d recommend it since it contains an essentials compilation of PowerShell common tasks and language specifics.Good reading indeed!

There are also other books that may catch your interest:

Feb 02

Running Adafruit Feather HUZZAH ESP8266 with external power supply (3.3V / 5V)

Usually you use a usb cable to power and programAdafruit Feather HUZZAH ESP8266 via the mini usb port:

But what if you want to use external 3.3V (or 5V) power supply? To which pin should you connect it?

Continue reading

Jan 10

Dynamic Objects in Active Directory

Sometimes we need to create users/groups/computers in Active Directory that will be used temporary (by a contractor, for testing etc.). The typical workflow is: Create > Use for a while > Delete. The deletion is manual and often these objects are being forgotten which poses some security risks.

It is little known fact that we can create the so called Dynamic objects (DOs, a.k.a. temporary objects) that get deleted from AD automatically when the associated TTL expires. Microsoft added this capability in Windows Server 2003. In fact the “Dynamic object” is an auxiliary class (OID = When linked to an object it adds some new attributes like the entryTTL (Entry-TTL) and ms-DS-Entry-Time-To-Die attribute.

Continue reading

Jan 05

WinRM would not listen on port 5985

The WinRM was configured to allow remote administration via a GPO but it wouldn’t let us connect with Enter-PSSession. The firewall rule was there passing the traffic on TCP port 5985.

Checking WinRM config showed something strange:

Listener [Source=”GPO”]
Address = *
Transport = HTTP
Port = 5985
Enabled = true
URLPrefix = wsman
ListeningOn = null

So WinRM was actually configured but wasn’t listening on any network interface. Why?

Continue reading

Jan 03

What is Add-PrinterDriver actually used for?

As of Windows 8.1 / Server 2012 R2 there is one beautiful cmdlet -Add-PrinterDriver. It dramatically simplifies driver/printer installation.

Naturally you will be tempted to install a driver from an .inf file like this:

But you will be blamed:

So it does not work as you/we may think. Sigh… So then what it is used for?

Continue reading

Dec 30

Running Linux on Windows 10


Often developers and related OPs need to test stuff on Linux (web, cli, .NET Core etc.). The typical approach was to spin up a Virtual machine (VM), install and configure a Linux distro and play with it.

Main Cons include: you need a hyper-visor software, enough RAM, fast hard drive, to fight with basic operations like cope-paste text and files between machines etc.

Well, good news! As of the Anniversary Update Windows 10 supports the so called “Windows Subsystem for Linux” (WSL). It allows you to run natively* most of the non GUI Linux stuff**on Windows without the overhead of a virtual machine.

Continue reading