Recently Microsoft released Windows XP Service Pack 2c (SP2c) to system builders. The new version of Windows XP has volume labels which are identical to the previous volume labels for Windows XP Service Pack 2b (SP2b).
Microsoft recommends that system builders do not use the volume label as a method of uniquely identifying media versions. For example, the CD volume label for both Windows XP Service Pack 2b and 2c for Windows XP Professional English OEM is listed as:
For Opened CD Sets: Use File Dates and Times
To determine whether a CD is from Windows XP Service Pack 2b or 2c, system builders should look at the file dates and times on the CD rather than the volume labels.
As an example, Setup.exe on a Windows XP Service Pack 2c CD will be dated July 27, 2007 at 5:00 AM.
For Unopened CD Sets: Use the COA
For unopened CD sets, the easiest way to verify if the product is Windows XP Service Pack 2c is the inclusion of the new Certificate of Authenticity (COA) label:
Small Manufacturer Pre-installed Windows COA
The latest small manufacturer pre-installed Windows COAs contain two Port-Holes™ near the middle of the COA with blue-green backgrounds. The Port-Hole on the left is an oval and the Port-Hole on the right is shaped like a Windows flag, each with individual paper fibers visible around the inside edges. (There may be variation to the shape due to manufacturing techniques.)
This COA is typically blue-green in color. However, in Asia they are available in rose, and for Windows Starter Edition installations they should be green.
Alternative Windows XP COA's
Large Manufacturer Pre-installed Windows XP COA (Twin Thread)
Windows XP COA (Dual Port-Hole)
Windows XP COA (Dual Blue-Green with Keyboard)
Windows XP RTM COA (Blue / Oldest COA)