Within about 60 seconds of when you launch the SecCheck SCU problem an instance of Notepad will be opened which will contain the SecCheck Text (raw) output. Review the very top of this file to verify which Service Pack has been applied to your system.
It should looks like one of the following:
Friday, February 24, 2006 8:32:56 PM UTC / Friday, February 24, 2006 3:32:56 PM Eastern Standard Time Operating System: WinNT Version 5.1.2600 "Service Pack 2", Type 0x01, Suite 0x0100, "2600.xpsp_sp2_gdr.050301-1519" == "Windows XP Professional Service Pack 2 (Build 2600)" System Name: "NEW-xxxxx" Last shutdown recorded in Registry: 2/24/2006 2:05:39 AM UTC Install Date recorded in Registry: 11/20/2004 11:08:12 PM Total physical RAM reported by system: 479 MB
Friday, February 24, 2006 2:17:39 PM UTC / Friday, February 24, 2006 9:17:39 AM Eastern Standard Time Operating System: WinNT Version 5.1.2600 "Service Pack 1", Type 0x01, Suite 0x0100, "2600.xpsp2.030422-1633" == "Windows XP Professional Service Pack 1 (Build 2600)" System Name: "xxxxxxx" Last shutdown recorded in Registry: 2/23/2006 10:16:59 PM UTC Install Date recorded in Registry: 2/26/2003 3:38:36 PM Total physical RAM reported by system: 509 MB
Wednesday, February 22, 2006 9:53:27 AM UTC / Wednesday, February 22, 2006 3:53:27 AM Central Standard Time Operating System: WinNT Version 5.1.2600 (nothing), Type 0x01, Suite 0x0100, "2600.xpclient.010817-1148" == "Windows XP Professional (Build 2600)" System Name: "XXXXXX" Last shutdown recorded in Registry: 2/21/2006 11:14:27 PM UTC Install Date recorded in Registry: 9/21/2005 1:37:03 PM
Friday, February 24, 2006 7:53:03 PM UTC / Friday, February 24, 2006 1:53:03 PM Central Standard Time Operating System: Win9x Version 4.10.2222 " A " == "Windows 98 Second Edition" System Name: "xxxxxxx" Install Date recorded in Registry: 3/7/02 9:16:02 AM Total physical RAM reported by system: 255 MB