Dollar Sign In Excel Cell’s name

The Dollar ($) in Excel formula indicates absolute reference. What does that mean?

It means that the value that immediately succeeds the dollar sign will not change.

In Excel a single cell can be used in 4 different ways:

Let’s take cell B4 as an example:

you can have:


No $ sign this one is relative. It will change if a column/formula that references this column is copied to a different cell.


If a cell references this column, the "B" will never change bit the "4" will change. Only the "B" is Frozen


If a cell references this column, The "B" will change but the 4 is frozen. So if you use this in a formula, the 4 is absolute.


If a cell references this column, it will NOT change if that cell is copied to a different cell. The whole cell is frozen.

Useful Links:

VMWARE : Could not open the client device. Check that the device exists…

check that the device exists

If you get this error “VMWARE : Could not open the client device. Check that the device exists and that it is not being used by another program” while trying to connect vsphere client to a CD-ROM try the following:

Run vsphere client as an administrator. Right click on the VSphere client icon and select "Run as Administrator"

That did it for me on Windows 10, hopefully this post will help someone out there.

Using Git on Windows


Download git for Windows here :


Change your "Start in" folder accordingly
set up git for windows

Third (optional)

Do this step only if you want to change default home that git for windows pulls from your system.

Add a windows environment for HOME and point it to the location of your new home folder.

Problem resolving .local domains from Linux

If you are having the following issue :

ping IP -> Success
ping NETBIOS -> Success
nslookup xyz.local -> Success
ping xyz.local  -> FAILURE

The solution is to edit /etc/nsswitch.conf and remove the text “[NOTFOUND=return]”

More on that here:
Avahi and dot-local addresses on Ubuntu

What is the location of Microsoft Windows’ Logon Scripts

Startup folder for a user is :

C:\Users\%USERNAME%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup

Startup folder for every user

C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Startup

Stop mysqld_safe Safely

After running “mysqld_safe –skip-grant-tables”  you may notice that the process is still running.
Instead of killing the process by running: kill -9 process ID
you can safely kill mysqld_safe by running the following command:

mysqladmin shutdown

Prevent iTunes from Launching When i Plug my iPhone

If you are annoyed by the fact that iTunes keeps starts everytime you plug in your iPhone then you are not alone.

Just turn that option off:

  1. Go to preferences



     2. Check OFF  “Prevent iPods, iPhones and iPads from synching…”



Delete all Emails in an Account from the Command Line Linux

Option 1


Option 2

cat /dev/null > /var/mail/root

Install TomCat on Ubuntu


Download Tomcat


Extract it to folder on your Ubuntu server


Set Up your environment variables (important)
open /etc/environment
copy and paste the following: (Make sure you use the proper paths for your system)
for example, in my system it looks like this: 


"source /etc/environment" 
to make the system recognize the newly added paths



change the permissions of the ".sh" inside the  apache-tomcat-8.0.33/bin directory
chmod +x *.sh


start tomcat by running

Nodejs from Node.js v0.12.7 To Version 4.0

Why the discrepancy in the version numbers?

Once upon a time there was just node.js then some people were unhappy with the speed of releases of node.js so they created io.js.

A few months later io.js converges back with Node.js 0.12.x into a unified Node.js 4.0.

Hence version Node.js 4.0 is born.

4.0 is the new 1.0
4.0 is the new 1.0 –

Delete WordPress posts from the database

First run some selects statement before you start deleting

SELECT * FROM wp_posts where post_status like '%XXXXXXXX%'
SELECT * FROM wp_postmeta
	SELECT * FROM wp_posts
	WHERE wp_postmeta.post_id = wp_posts.ID

Run the actual delete (Always do a backup first)

delete * from wp_posts post_status like '%XXXXXXXX%'

-- Delete orphan records from the wp_postmeta table
delete * FROM wp_postmeta
	SELECT * FROM wp_posts
	WHERE wp_postmeta.post_id = wp_posts.ID

Turn off console-kit-daemon Centos / Ubuntu / RedHat


cd /usr/share/dbus-1/system-services/
mv org.freedesktop.ConsoleKit.service  org.freedesktop.ConsoleKit.service.old

make[1]: *** [wav2swf] Error 1 while installing swtools

Run make clean
apt-get install bison
apt-get install flex
make install

Install zlib ubuntu

app-get install zlib1g-dev

undefined symbol: php_json_decode_ex in Unknown on line 0 – in Ubuntu

Make you sure that this line comes before your newly added extension in php.ini

then add your extension

The order matters

Upgrading Request Tracker to the Latest Version

Step 1

Backup your current database.

mysqldump rt4 > rt4.sql 


Download the latest version and unzip it to a folder
(NOT The Destination folder). You can unzip it to your /tmp folder as an example.


Access the folder whee you unzip the files and make sure you run the following commands:

make testdeps

If this fails, make sure you run the following command or install the dependencies manually.

make fixdeps

Once you make sure that your last line says :”All dependencies have been found.” move on to the next step

Step 4

run the following config file (Ubuntu):

./configure --with-web-user=www-data --with-web-group=www-data --with-db-type=mysql --with-db-host=localhost 
--with-db-port=3306 --with-db-rt-host=localhost --with-db-database=rt4  --with-db-rt-pass=XXX --prefix=/opt/rt-X.X.X

Step 5

run make testdeps.

Step 6

run make fixdeps.

Step 7

run make upgrade (If everything goes well, you will be prompted to upgrade the database)

Step 8

run make upgrade-database.

Step 9

Fix your permissions if needed (ubuntu):
change www-data to the user that your server is running as
chown www-data.www-data var/* -R
chown root.www-data etc -R

Step 10

Copy the etc/ from the old install to the new install.

Step 11

Move all plugins from the old install to the new install

Step 12

Make sure that you check you email fetching program to make sure that you pointing to the new directory(if of course you changed it).

Step 13

Start apache

Lastly please read the docs (If you can) I am not really sure that i would call that a documentation. It is more like a list of class and methods and their functions.

Compile SWFTools in Ubuntu

1. Prerequisites
Make sure that you install the following libraries:

apt-get install libgif-dev

apt-get install libjpeg-dev

apt-get install libfreetype6-dev

2. Compile swftools



make install

Change all Files to 644 and all Directories to 755 Linux

find . -type f -print0 | xargs -0 chmod 0644 

find . -type d -print0 | xargs -0 chmod 0755 

Unable to create directory wp-content/uploads/2014/10. Is its parent directory writable by the server?

If you try all the possible permissions permuation and you are still unable to upload file to your site, you may need to double check your upload_path
via the options link listed below:

Navigate to 
and make sure that your upload_path is corrent

Running PHP as Apache Module mod_php

If you take a look at your Apache module folder, you will notice that most modules start with “mod_” for some reason the people who compiled the php apache module felt the need to name it Yet, they still refer to it as mod_php, which it is but i only have one thing to say to them “please name your damn module appropriately”.

Well if you want to run PHP as an Apache Module, you will need to make sure that you add (or uncomment) the following line located in your http.conf file.

LoadModule php5_module        modules/

Please assure that you have the inside the modules folder.