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Mailenable : Webmail showing Server communication failure

  Many Mailenable users are familiar with the error " Server communication failure. Please refresh your browser and try again. ". This error shows when you try to send an email using Mailenable webmail. In today's lesson, we will learn how to fix this. In general, there are two ways to resolve this problem: STEP 1 : The Mailenable webmail is mostly compatible with 32-bit applications written in .NET 2.0. To begin with, you can try this. Just go to MailenableAppPool and in Advanced settings change the .NET version to 2.0 and 32 bit as TRUE. STEP 2 : If the .NET version is already 2.0 and the error still occurs, then follow these steps. Go to Mailenable Bin path Search for " MeInstaller.exe " file > Run it as Administrator Now Select Option 13. Set .Net Framework version for web application > Next Now it will ask for the ASP.Net configuration details and select the appropriate one you want to use > Execute Hopefully, this will fix the problem.

How to fix Trust Relationship issue in Windows (without System Reboot)

  Hello Readers, today we are going to learn how to Fix trust relationship issue between the workstation and the domain. But before jumping into the solution, we need to learn the concept of Secure channel. What is a Secure Channel ? Before understanding the trust relationship issue, you will need to know what is a Secure channel .  Whenever you add a computer or client machine to an Active Directory domain, your computer account gets created in Active Directory. Secure Channel helps to make the communication between the client machine and DC (Domain Controller), Example : Replicating Group Policies. Always remember in a Secure channel the computer authentication takes place and not the User Authentication So for this Authentication Password is required. Once computer is joined to the domain a password for authentication is proposed to the Active Directory By Default, Computer account password change is initiated by the client computer in every 30 days . This can be modified in Group P

GIT : How to remove untracked files in git

There might be several conditions where you have started editing a file in git but then you realize its not needed any more and want to roll it back.  Such files will be showing in untracked files list in git as show below when you run git status command. Today we will learn how to remove such untracked files in git.  To fix it you can run the below command :  git clean -f 

Linux Tip : How to fix Route issues

Today we are going to learn how to fix route issues on Linux. Suppose you have 2 NIC interface (one is for public traffic - 100 GBPS Link and other one in Private interface for private communication 10 GBPS Link ). What is the exact issue ? Initially our customers reported that they were unable to reach internet on the box (They tried performing ping 8.8.8.8 -or- ping google.com). It was not working via both IP and domain name even tried with browser. So lets begin the troubleshooting : Step 1 : Replicate the issue from your side, because we need to be 100% sure before deep diving. Step 2 : We were able to replicate the same. It was 100% packet loss. So now we need to check if the public interface is up and running or not . Our public interface is eth1 so run command : ip a This will show you if interface is UP / Down. Eth1 was up and running here. Step 3 : Next I was interested to see how is the traffic going out - is it crossing any single hop or not , whether Gateway is reachable

Linux Useful commands

Here are the list of some useful Linux commands that's used on a day-to-day work and are equally important for interview purposes.  1. How to check memory usage free -h -h is to make the result readable by humans. 2. How to check disk usage df -h 3. How to check CPU Usage top 4. How to quickly find the process id of a program pgrep <ProcessName> 5. How to find the Linux Kernal version uname -r amar@LPF22E8MA:~$ uname -r 4.4.0-19041-Microsoft 6. How to find the Operating System (OS) version cat /etc/os-release lsb_release -a amar@LPF22E8MA:~$ cat /etc/os-release NAME="Ubuntu" VERSION="20.04 LTS (Focal Fossa)" ID=ubuntu ID_LIKE=debian PRETTY_NAME="Ubuntu 20.04 LTS" VERSION_ID="20.04" HOME_URL="https://www.ubuntu.com/" SUPPORT_URL="https://help.ubuntu.com/" BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/" PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy" VERSION_C

PowerShell Tip : How to copy a file remotely using WINRM

Today, we are going to see how to copy a file to remote destination using WINRM. Traditionally SMB Protocol (File Sharing \\Servername\C$) was used to transfer the files but nowadays you will find SMB Protocol disabled on some servers so you will require firewall changes to perform that.  On the other hand WINRM Protocol 5985 is mostly open for Powershell Remote sessions, so we will use that to transfer the files. Lets get started : Step 1 : Create a PS Session for that server  $Session = New-PSSession -ComputerName <ServerName> Step 2 : Use Copy-Item with -ToSession to transfer the file using WINRM Copy-Item -Path C:\Scripts\Amar\TestFile.txt -ToSession $Session -Destination "D:\" TestFile.txt file will get copied from local system to the D Drive of the remote server. Happy Learning :)

ActiveDirectory : How to find unused AD User accounts using Powershell

Today we are going to learn how to remove an AD User which is not Active since a long time lets say 1 year. As a part of Server hardening best practices, you should always run checks to remove the disabled or orphan accounts from Active directory. We will be using the Active Directory module in Powershell to perform the activity : CODE :  $Date =(Get-Date).AddDays(-365) Get-ADUser -Filter 'LastLogondate -le $Date' -Properties LastLogonDate | Select Name, LastLogonDate To remove the ADUser use : Remove-ADUser -Identity "<SamAccountName>"

Linux Tip : How to Switch user as root if you have Sudoers access

Today we will see how one can become a root user if he / she has sudoers access. In some organizations if you try to switch user to root ( sudo su - root ), you may see error like below : Sorry, user <username> is not allowed to execute '/bin/su - root' as root on <hostname> But you can try other method to switch as root user. Lets look into those steps. Method 1 : Type  sudo vi -c '!bash' in the command line console and that's it. Method 2 :   Type   sudo vi a.txt  in the command line console , it will open vi editor just press ESC (Escape) and then :sh and Enter Hope you all enjoyed this little hack, do share your queries in the comment box below.

PowerShell Tip : How to find Host node name from inside the VM

Let's assume a scenario where you are inside the Virtual Machine but you want to the know the Host node name. Unless you maintain some inventory management system, it would be a troublesome job to identify the same. Here is how this can be achieved using Powershell. Just run the below one-liner on the VM : (Get-item "HKLM:\SOFTWARE\Microsoft\Virtual Machine\Guest\Parameters").GetValue("HostName")

Kubernetes and Docker Notes

What is Kubernetes ? Kubernetes (K8s) is a container orchestration tool, which helps to manage, deploy and scale containers like Docker etc. Kubernetes was designed by Google using Go Lang. What is Docker ? Docker is an open source project that automates the deployment of applications inside containers. What are Containers ? ⚡Containers are basically layer of Base image and application image, stacked together with all their necessary dependencies and configuration. ⚡Containers are portable and scalable.  Docker Public Repository :   https://hub.docker.com/ How to install Docker on Windows  ? Note : Hardware Virtualization should be enabled on the host box in order to install Docker.  1. Go to the link =  https://docs.docker.com/desktop/windows/install/ 2. Download and Install the application To verify if installation was successful or not, just type :  docker run hello-world while running the above command I got the below error, it was because I didn't run Docker desktop app with

Powershell Tip : How to fetch public ip using Powershell Console

There are several ways to fetch your public ip like below : But today we are going to see the simplest way to fetch the same via Powershell console : Command : (Invoke-WebRequest -uri "http://ifconfig.me/ip").Content

How to check if SPF Record is valid or not ?

Before starting, lets understand what is SPF Record and its uses ? SPF Record is a Sender Policy Framework record. It is used by the mail servers to identify if the mails are coming from an authorized hosts or not. This helps to prevent spammers from sending mails using the Fake From address of your domain. Always avoid to keep multiple SPF Records for a domain. You can use the below domains to create or check if SPF Record is valid or not : 1. Create and check SPF record online (spf-record.com) 2. Free SPF Record Checker - Check SPF Record - SPF Record Lookup - DMARCLY 3. SPF Query Tool (kitterman.com)