Tag Archives: windows

How to generate a large files for testing

You can generate large files for testing on both Linux and Windows machines without having to leverage a 3rd party utility.


In Windows, you can use the fsutil utility to create a new file with a defined number of bytes. In this case, the following command will generate a 1 GB file. The contents of the file will consist of spaces.

fsutil file createnew "C:\Users\<username>\Desktop\sample.txt" 1073741824


In Linux, you can use the dd utility. In this case, this command will create a 1 GB file filled with 0s. The bs parameter is the block size and count is the number of blocks to create.

dd if=/dev/zero of=testFile_dd bs=512M count=2

Find listing of open ports on Windows

Want to see what ports are currently listening for connections on your machine?

To quickly find a list of open ports listening for connections, execute the following netstat command (this will show the Protocol, Local Address (source port), Foreign Address, State, and Process ID):

netstat -ano |find /i "listening"

To quickly ifnd a list of ports with established connections, enter the following command  (this will show the Protocol, Local Address, Foreign Address, State, and Process ID):

netstat -an |find /i "established"


Here is a complete listing all of the netstat switches

Displays protocol statistics and current TCP/IP network connections.

NETSTAT [-a] [-b] [-e] [-f] [-n] [-o] [-p proto] [-r] [-s] [-t] [interval]

-a Displays all connections and listening ports.
-b Displays the executable involved in creating each connection or listening port. In some cases well-known executables host multiple independent components, and in these cases the sequence of components involved in creating the connection or listening port is displayed. In this case the executable name is in [] at the bottom, on top is the component it called, and so forth until TCP/IP was reached. Note that this option can be time-consuming and will fail unless you have sufficient permissions.
-e Displays Ethernet statistics. This may be combined with the -s option.
-f Displays Fully Qualified Domain Names (FQDN) for foreign addresses.
-n Displays addresses and port numbers in numerical form.
-o Displays the owning process ID associated with each connection.
-p proto Shows connections for the protocol specified by proto; proto may be any of: TCP, UDP, TCPv6, or UDPv6. If used with the -s option to display per-protocol statistics, proto may be any of: IP, IPv6, ICMP, ICMPv6, TCP, TCPv6, UDP, or UDPv6.
-r Displays the routing table.
-s Displays per-protocol statistics. By default, statistics are shown for IP, IPv6, ICMP, ICMPv6,  TCP, TCPv6, UDP, and UDPv6; the -p option may be used to specify a subset of the default.
-t Displays the current connection offload state.
interval Redisplays selected statistics, pausing interval seconds between each display. Press CTRL+C to stop redisplaying statistics. If omitted, netstat will print the current configuration information once.

Notes: Here is a great resource with more in-depth details on the command: http://www.petri.co.il/quickly_find_local_open_ports.htm

How do I create a symbolic folder in windows?

1. Open up a command prompt (Start->cmd)
2. Navigate to the directory where you want your folder.
3. Execute the following command: mklink /D foldertoredirect C:\path\to\another\directory

That's all that is to it!

Note: This works for creating FTP directories that need to redirect to another.

DNS name does not exist. - Windows Activiation

When activating Windows (in this case Server 2008 R2), you receive the following dialog box:
"Code: 0x8007232B Description: DNS name does not exist."


If you receive this error, you are more than likely using an ISO from the Microsoft Volume Licensing Center when in reality you want to just use your license key (the OS is looking for your KMS server (Key management services), and if you don't have one, then you receive this DNS failure).

How to:

  1. Click Start, click All Programs, click Accessories, and then right-click Command Prompt.
    1. Click Run as administrator.
  2. Execute the following command (where the X's are your license key :)):
    1. slmgr -ipk xxxxx-xxxxx-xxxxx-xxxxx-xxxxx
  3. You should get a popup saying the key has successfully been installed after you execute the command (there is a delay).  Once you see that, go ahead and activate windows as you normally would.
    1. Start->right click properties on My Computer->Activate...

Windows cannot access the specified device, path, or file.

If you try to run an executable and you receive this dialog box:
"Windows cannot access the specified device, path, or file. You may not have the appropriate permissions to access the item."

Here is the fix. Right click on the executable, and click on the Unblock button.

Done! 🙂