Articles

Can 'Unauthenticated' tag on NIC result to a broken secure channel?

Couple of days ago I noticed a strange behavior on network adapter of dozens of clients in my environment. The users were not able to authenticate to their workstations, throwing secure channel error. When one of the helpdesk administrators informed me about this issue, I thought it might be a typical problem of operating system including incorrect DNS configuration or duplicate names, but this was strange because basically everything related to secure channel were in place. Computer accounts were enabled in ADUC, DNS records existed, logintimestamps were updated and etc. So I tried digging in the problem to see what I can find.

Why NTDS size is different on different Domain Controllers?

Ever wondered why size of Active Directory database is different on domain controllers? You might ask yourself if Active Directory supports MultiMaster technology, then all objects reside in database on all domain controllers, so if that is true, why the size of database (NTDS.DIT) is completely different on one domain controller to another?

Limit Active Directory user login to 1 session

User authentication is one of the key principals of Active Directory as a directory system. It is safe to say that when user authentication does not exist in an Active Directory environment, then there is no need to have an Active Directory in our organization.

The auditor of auditors: 'LepideAuditor Suite'

Today, in modern days of technology, the concept of auditing has become one of the interesting facts in Information Technology (IT). Back in days, when I was probably playing with my SNES, the concept of auditing was so hard to follow with built-in applications and consoles, but today, you can find many applications which either covers a specific part of auditing or support a huge number of services and applications. Among them, it is rare to find a solution which covers a whole range of services and audits, but ‘LepideAuditor Suite’ is one of those rare. In this article we will talk about this application.

Protect your domain against WannaCry malware

As you all know the #wannacry malware hit the whole world in the last few days. The vulnerability behind this malware was leaked out by ShadowBrokers. Since the spreading rate of this vulnerability is greatly increasing, it is considered an obligation to prevent from this.

‘List Object Mode’ in Active Directory, a myth or future settings?

After long delay of being absent, I managed to fetch some time in order to pen down an article and share my thoughts about on of the features of Active Directory which has been always in total darkness for me. ‘List Object Mode’.

Fix Group Policy error 1058

Bulk change specific permissions for users

A friend of mine recently had problems regarding uploading certificates to GAL. As a matter of fact the users were unable to upload certificates when they choose "Publish To GAL". In this case the most errors you get is "Microsoft office Outlook was unable to publish your certificates. The server may be offline or your certificates may be invalid". 

Create Shadow Groups (Dynamic Groups) in Active Directory

Recently I faced a request from a client wanting a Dynamic Security Group in Active Directory which automatically update its members.. However we do have the concept of dynamic objects in Active Directory (I promise to speak on that on another article), but this one was completely different. The client wanted to have a security group which automatically removes the disabled users from it. So I started a lovely conversation with my lovely friend PowerShell.

Am I locked out? Where? How?