===== Downloads =====
Before starting a ClearOS Enterprise installation, you will need to download the installation media (details are in the next section).  To verify the integrity of the download, you can check the MD5Sum of the file.  What is an MD5sum?  To make a long story short, an MD5sum is a simple way to verify the integrity of a downloaded file.

For Windows, you can often use CD burning software to verify an MD5sum.  Alternatively, you can download and install the free [[http://www.md5summer.com/|MD5Summer]] tool.  In Linux, you can use the command line [[http://www.clearfoundation.com/docs/man/index.php?s=1&n=md5sum|md5sum]] command.

===== Install Methods =====
There are three ways to install or upgrade ClearOS Enterprise:

   * Bootable CD
   * USB key (requires Internet access)
   * PXE-enabled network card 

==== Bootable CD ====
The ClearOS software can be installed from a CD-ROM drive.

  * If necessary, change your BIOS settings to run bootable CDs
  * Insert the ClearOS CD
  * Turn on your target system

  * [[http://www.clearfoundation.com/component/option,com_ionfiles/fileid,103/func,download/|ClearOS 5.1 Release Candidate 1 ISO image]]

==== Bootable USB Key ====
Installing via a USB key is also possible. Only the first part of the install process actually runs off of the USB key, so you only need a small 20 MB key. The majority of the ClearOS installation is done over the network. First, you need to download the USB image: 

  * [[http://download.clearfoundation.com/clearos/enterprise/5.1/images/diskboot.img|diskboot.img]]
  * [[howtos:burning_an_iso_image|How to burn an ISO image]]

You should then use desktop tools to image your USB key with this file. Keep in mind, you are not copying the diskboot.img file, but imaging your USB key with it. For those familiar with the Linux command line environment, you can use the **dd** command. 

==== PXE Boot ====
If you have a PXE Boot environment on your network, you can also configure it for ClearOS.  If you do not have this environment, use the CD or USB key methods.  Alternatively, you can go through the trouble of configuring your own environment by following the [[Howtos:Installing Via Pxe Enabled Network Card]] Howto.

===== Next Steps =====
Once you have booted the installer, you can follow the [[Installation Wizard|installation wizard]].

<note warning>The contents of all your hard disks on the target computer will be completely erased. This may include any attached hard drives like USB and external SATA</note>