The 5 Windows XP Versions

Full, Upgrade, OEM Branded, OEM unbranded, and Recovery

OEM = Original Equipment Manufacturer

What to buy?  This is an important decision.  You will first need to understand WGA (Windows Genuine Advantage) Activation and Validation.  For more details, see Microsoft's Licensing page, their Licensing FAQ , Licensing Options, required Licensing Documentation - also see our Validation page.  If you are involved with licensing WinXP on multiple machines - see Microsoft's "SAM" page (SAM = Software Asset Management)

Where to buy: OEM Unbranded all Versions

Deciding which to Buy :

Case 1) you have a new PC and do not intend to move to another machine and do not intend to upgrade the CPU or Motherboard - buy the OEM unbranded or the Upgrade (Retail). 

Case 2)  you have a PC which you will keep, but plan on getting a 2nd PC - buy the OEM unbranded or the Upgrade (Retail). This way you will have a licensed copy of XP on BOTH machines for about the same price as one Full version !!  If you have 3 people in your household that all need XP then buy a 3-pack of the OEM unbranded version.

Case 3) you might be moving to another machine or upgrading your CPU or Motherboard in the future - buy the Full (Retail) version !!!  It is the ONLY version that will allow this !!!

Case 4) FREE - use any WinXP CD that you can get that does not require activation - load SP2 on it, download and install the full version of "Autopatcher", and from that point on run an Autopatcher update every few months.  The only disadvantage is that if your system says "insert Windows XP SP2 CD" - you will not have one to insert - but you can usually get the files elsewhere or run the latest Autopatcher update to get rid of that request.

The 5 Versions
*** o
nly the Retail Full Version allows you to move Windows from one PC to another !!

Full - also called Retail Full version - most expensive, can be transferred to another machine, so long as it is uninstalled from the old machine.  If you lie and do not uninstall it - then the old machine will run, but will act as any other machine running a pirated version (i.e. it will not validate with WGA and will only be allowed to receive critical updates).  CAN MOVE FROM MACHINE TO MACHINE (just make sure you uninstall then reinstall, and re-activate.  You may need to call Microsoft for re-activation)!!

Upgrade - also called Retail Upgrade version - much less than Full - and usually just a tad more than OEM unbranded.  The setup.exe will not run from DOS, but all you have to do is boot from the CD, start installing, and when XP says that it doesn't detect an operating system and to please insert an OS disk, put in your Win98 disk.     CANNOT MOVE FROM MACHINE TO MACHINE and CANNOT Replace/Update CPU or Motherboard (will fail validation when running Windows update) !!

OEM Branded - comes installed with a new PC (branded OEM).  Functionally identical to unbranded OEM.  Can only be installed on ONE MACHINE.  After that, even if you have a fire or a complete system failure and need to get a new machine . . . you will have to but a new copy of Windows XP.  OEM = OnE Machine.   CANNOT MOVE FROM MACHINE TO MACHINE and CANNOT Replace/Update CPU or Motherboard (will fail validation when running Windows update) !!

OEM UnBranded - bought separately (not with a PC).  Functionally identical to branded OEM. Can only be installed on ONE MACHINE.  After that, even if you have a fire or a complete system failure and need to get a new machine . . . you will have to but a new copy of Windows XP.  OEM = OnE Machine   CANNOT MOVE FROM MACHINE TO MACHINE and CANNOT Replace/Update CPU or Motherboard (will fail validation when running Windows update) !!

Recovery CD - ecomes with new PC, and contains an "image" of the hard drive, including Windows XP and all the software drivers and utilities that come with the PC.  Very restrictive because you need to wip out the entire drive, then the image is refreshed.  Cannot be used when the system asks you to "insert the Windows XP CD".  Cannot be used to refresh certain XP files that are missing or corrupted, unless you blow everything away and start over.  A terrible idea and a terrible way to go !!!  CANNOT MOVE FROM MACHINE TO MACHINE and CANNOT Replace/Update CPU or Motherboard (will fail validation when running Windows update) !!

If Windows will not Activate or Validate

In other words, either a post-installation Activation procedure, or the WGA - (Windows Genuine Advantage) validation tool fails to receive a positive response from the Microsoft Avtivation/Validation servers.  This means they think you are running a pirated copy of Windows.  Should this ever happen to you, and you are legit - you may have to "prove" ownership. 

First, go to the Microsoft Genuine Advantage Diagnostic Support Page, download the the Microsoft Genuine Advantage Diagnostic Tool. The  and run it to get a report on the Genuine or non-Genuine status of your software.  If you are legit but can't successfully Activate or Validate - you are supposed to retain the following 4 items and they will probably ask you to furnish them

What versions of Windows are Certain to be "Valid"

You would think that "any" version that you buy will be valid.  However, OEM CD's  .  .  .  believe it or not  .  .  .  will not validate !!  The exception is "unbranded OEM" CD's which will validate.

OEM CD's and Validation  -  OEM vs Retail WinXP  -  OEM can only do a clean install or a Repair (in place) install (go Here for instructions) - it cannot do an "Upgrade".  An OEM (Original Equipment Manufacturer) version of Windows is one that comes with a new Computer.  It may be preinstalled or included as a CD, or both.  DO NOT BUY A "Branded OEM CD" - it is meant only for the PC it was originally installed on !!!  You can install it, but you will never be able to activate and validate.  The license for an OEM version of Windows XP is tied forever to the first computer it was installed and activated on.

Also, if you make a major hardware change, such as installing an entirely different motherboard, the license is no longer valid. That is one reason OEM versions cost less... no support directly from Microsoft.

NOTE:  As of February 28th 2005, all COA keys affixed to the computer case will have internet activation disabled. A mandatory phone call will be prompted to receive an override key after answering a series of questions which manually verify them as legitimate. This does not affect unbranded OEM versions purchased with authorized hardware through legitimate vendors. Branded OEM versions [I.E. Dell, HP, Gateway, etc..] purchased from eBay and other similar vendors will be affected and may lose the ability to activate the questionable copies.

Branded OEM vs Unbranded  -  the idea behind OEM Windows s that it comes with a PC (it is "branded").  However, surprisingly, you can get unbranded OEM copies (NewEgg sells several OEM versions at  ) which work like the full version except that you cannot install it as an upgrade. But that's OK - just do a fresh install, and if you need to reisnayll then that is no problem).  The only limitation is that it will not upgrade a previous version - but there is no reason to ever want to do that. 
CON:  You also "supposedly" can never move it to another machine once it is installed. 


The following Windows OEM CD information was found at Tek-Tips

ALL OEM copies can only be installed clean: (that is, the hard drive must be formatted before XP OEM can be installed). They cannot be used to perform an upgrade of an existing Operating System so make sure
you back up all necessary data and files BEFORE installing XP OEM, since the format of the Hard Drive will erase ALL data on it.

There are two types of OEM CDs:
1) an OEM version created by a system manufacturer. These copies are usually "BIOS-locked", and can only be used on the exact machine they were created for.
2) a "FULL OEM", or "FULL OEM DSP". These may be installed on any IBM-compatible machine. These may or may not be provided with a factory-built machine, but are usually purchased separately for installation a home-built machine.

You will be making a trade-off in buying an OEM version. YOU will trade the ability to upgrade an existing installation of Windows (and save
your data and programs) and the legal right to install the copy on a new machine, (if you should change your old machine for a new one), for a
big savings in the initial cost of Windows XP.

NOTE: OEM versions must legally be sold along with a hardware item, but in many cases this hardware item may be a power-cord (usually a $1) or mouse (they might even give you the mouse to satisfy Microsoft's
licensing requirements)

Three other issues that need to be emphasized about an OEM license:

1. You will receive no support from Microsoft. You will be referred to the original OEM licensee.
2. You cannot upgrade the FULL OEM DSP version. When longhorn or whatever appears this will not be a qualifying license.
3. Currently you can transfer (no, not two copies) a non-OEm license to a new machine. You remove XP from the first machine and the license will transfer to the new machine. You call Microsoft and they will issue you a new activation code. You cannot do this with the OEM license. It is for one machine only, the original machine. You will not be issued an activation code for a new machine.
4. You can upgrade the RAM, hard disk and other devices. And use the phone option to re-activate. The question is whether the OEM installation is fundamentally the same after the upgrade


XP OEM Version

Microsoft OEM software is a full version (non-upgrade) which includes the CD-ROM, the Certificate of Authenticity (COA), and the product key codes. These elements are all you will need to load and run the software. The software runs exactly the same way as the full retail version. OEM is a full version that is only supported by the computer manufacture that sold it to you, not Microsoft.  The differences between OEM and Retail are: 

Upgrade with an OEM CD - sorry, it's Impossible

The OEM CD is designed to prevent this by checking for existence of Windows on your PC.  With an OEM disk, if you try to install WinXP over Win98-ME-2000, etc. you will get a message that the upgrade is not allowed. OEM CD's do not allow Upgrades !!!  It states on the on the OEM CD "For Sale Only With A New PC".

With Win98 there was every reason to upgrade, and it was relatively easy to get around the simplistic OEM upgrade protection (see Win98 OEM upgrade).  I am not advocating hacking, but in many cases you may need to reinstall or install over an existing version of Win98 - and there is no reason that you should not be able to use the OEM CD that you paid for to do that.  You may have had Win95 or were reinstalling over a previous version of Win98 and did not want to lose your settings, programs, etc.

The same need for upgrading with an OEM CD with WinXP exists.  Unfortunately, no one has figured out how to do it !!!

However, there is a very good reason for NOT upgrading with WinXP.  Although you may want to keep your settings, programs, etc - it is such a dramatically different Operating System, that it is best to simply wipe the drive clean of Windows and install XP fresh.  It will take a while to reinstall all your drivers and programs - but it will be well worth it.  A clean install will remove all the thousands of unwanted dll's, hlp's, etc.  It will also run much faster since the baggage is gone !!

Recovery CD's

You cannot run an XP setup routine from a recovery CD !!   Therefore almost no one is dumb enough to try and sell one of these - but if you see one for sale - walk away !!!

This is just an image of a pre-installed system much like one created with a program like Norton Ghost or Powerquest's Drive Copy.  When run it will load that image to the hard drive essentially reverting the system back to the condition it was in when it was sold.  Recovery CD's come with some computers, such as HP, Compaq (now owned by HP), etc.  

Most recovery CD's have two options:  to reformat the drive and copy the entire image,   or you can select only to copy over the Windows XP operating system and the drivers.  The CD's include XP and the drivers for the motherboard, sound card, video card, etc.  Since they normally do a destructive install where everything is wiped out - they are to be used only for an absolute emergency !!

Retail Versions:   Full vs Upgrade - Full (expensive) and Upgrade (much less - just a bit more than OEM unbranded)

Get the Upgrade version !!!  There is no difference (if you do it right - here we show you how)

The Retail version of XP comes in two flavors, full and upgrade, both are supported by Microsoft. They are the same thing functionally !!  However, there are some differences:

Clean Install using Retail Upgrade Version

the upgrade version expects you have an older version of Windows installed already - so the setup.exe will not run from DOS !  The workaround is to configure your BIOS (your PC's setup routine) to boot from CD, then boot from the XP CD-ROM and let it start installing. When XP says that it doesn't detect an operating system and to please insert an OS disk, put in your Win98 disk.

If your PC will not boot from CD, then either install Win98, then run the upgrade - or download the six Windows XP boot disks from Microsoft.  

Boot Disk download pages:   XP Home     XP Pro


Windows versions that allow the XP Upgrade version to complete Installation

Previous Version Windows XP
Home Edition
Windows XP
Windows 3.1 NO NO
Any Evaluation Version NO NO
Any Server Version NO NO
Windows 95 NO NO
Windows 98/Windows 98 SE YES YES
Windows Me YES YES
Windows NT 3.51 NO NO
Windows NT 4.0 NO YES
Windows 2000 Professional NO YES
Windows XP Home Edition   YES
Windows XP Professional NO  


How to Tell which Version you Have - the "Pid"

Windows XP uses a file called setup.ini that is located in the I386 folder on your installation CD. The file controls how the CD acts, for example, is it an OEM version or retail version and so on. Find your setupp.ini file in the i386 directory on your XP CD. Open it with Notepad of similar.  You will see the following two lines (your ID will vary from these examples, of course):


The Pid value is what we're interested in. There are special numbers that determine if it's a Retail, OEM, or Volume License edition (corporations buy volume licenses). 

The Pid number is made from two parts: 

The actual Pid values can be any of the following:

Burning an XP CD and editing the Pid

You can burn a CD and mix and match these values. For example, you could make a Windows XP CD that acted like a Retail CD, yet accepted OEM keys.  Or you can leave them as is.

For example, if you wanted your CD to be a regular Retail CD that takes Retail keys, the last line of your setupp.ini file would read:


And if you wanted a Retail CD that took OEM keys, you'd use: