randomly my computer screen goes blank and says bad pool caller. i read online that i should unplug some usb ports because that may have been the reason. i unplugged my printer and it hasnt happened so far. if it does what should i do?

We will need some more information. What version of Windows are you using? Are you getting a BSOD (blue screen of death) error message? If so, what is the error number and the exact error message?

You should look in Device Manager too to see if there are any errors. Right click on My Computer > Properties > Hardware > Device Manager - look for yellow and red warning symbols.

there are no yellow and red warning symbols, im running xp pro sp2, i dont have the exact number and if i get the blue screen of death again then i will get the number

Well, if it happens again, we'll need the number and error message. In the meantime, you might want to make sure the system is clean of heat trapping dust and dirt, and clean of malware too. If you don't have an arsenal of anti-malware tools, see Cleaning Out Malware.

i got the blue screen of death at around 2 today, when i get it. it happens at random and is very inconsistant. i got the number at it is


STOP: 0X000000c2 (0X00000041,Ox85644000,0x0004E9B,0x0003BEDF)

Thanks for the help DAL
but should i just reinstall windows. would i loose all the windows upgrades i have downloaded?

As I mentioned a couple times, we need the error code AND error message.

See How to interpret "Stop 0x000000C2" Error Message and BSOD Diagnosis for more information.

If the text is consistently bad pool caller, that typically refers to a bad hardware driver. Have you recently made any hardware changes?

i just built this computer so all the hardware is brand new.

Debugging Details:
------------------


BUGCHECK_STR: 0xc2_41

CUSTOMER_CRASH_COUNT: 1

DEFAULT_BUCKET_ID: DRIVER_FAULT

PROCESS_NAME: vsserv.exe

LAST_CONTROL_TRANSFER: from 80547c2d to 804f9deb

STACK_TEXT:
b9ef8b50 80547c2d 000000c2 00000041 8516a000 nt!KeBugCheckEx+0x1b
b9ef8b90 8054a49a 8516a000 ba361dc8 ba361dc8 nt!MiFreePoolPages+0x8b
b9ef8bd0 8054a95f 8516a000 00000000 b9ef8c08 nt!ExFreePoolWithTag+0x1ba
b9ef8be0 ba361663 8516a000 00000000 ba360519 nt!ExFreePool+0xf
WARNING: Stack unwind information not available. Following frames may be wrong.
b9ef8c08 ba3605a7 00000000 00000000 00000000 regspy+0x1663
b9ef8c40 804ef095 85708778 00000000 806e4410 regspy+0x5a7
b9ef8c50 8057e70a 8520b7f8 85440158 8520b788 nt!IopfCallDriver+0x31
b9ef8c64 8057f56d 85708778 8520b788 85440158 nt!IopSynchronousServiceTail+0x60
b9ef8d00 805780c2 00000270 00000000 00000000 nt!IopXxxControlFile+0x5c5
b9ef8d34 8054086c 00000270 00000000 00000000 nt!NtDeviceIoControlFile+0x2a
b9ef8d34 7c90eb94 00000270 00000000 00000000 nt!KiFastCallEntry+0xfc
012ffc0c 00000000 00000000 00000000 00000000 0x7c90eb94


STACK_COMMAND: kb

FOLLOWUP_IP:
regspy+1663
ba361663 ?? ???

SYMBOL_STACK_INDEX: 4

FOLLOWUP_NAME: MachineOwner

MODULE_NAME: regspy

IMAGE_NAME: regspy.sys

DEBUG_FLR_IMAGE_TIMESTAMP: 43340c5d

SYMBOL_NAME: regspy+1663

FAILURE_BUCKET_ID: 0xc2_41_regspy+1663

BUCKET_ID: 0xc2_41_regspy+1663

Followup: MachineOwner
---------

eax=f771f13c ebx=8516a000 ecx=00000000 edx=00000000 esi=8108421c edi=c0428b50
eip=804f9deb esp=b9ef8b38 ebp=b9ef8b50 iopl=0 nv up ei ng nz na pe nc
cs=0008 ss=0010 ds=0023 es=0023 fs=0030 gs=0000 efl=00000286
nt!KeBugCheckEx+0x1b:
804f9deb 5d pop ebp
ChildEBP RetAddr Args to Child
b9ef8b50 80547c2d 000000c2 00000041 8516a000 nt!KeBugCheckEx+0x1b (FPO: [Non-Fpo])
b9ef8b90 8054a49a 8516a000 ba361dc8 ba361dc8 nt!MiFreePoolPages+0x8b (FPO: [Non-Fpo])
b9ef8bd0 8054a95f 8516a000 00000000 b9ef8c08 nt!ExFreePoolWithTag+0x1ba (FPO: [Non-Fpo])
b9ef8be0 ba361663 8516a000 00000000 ba360519 nt!ExFreePool+0xf (FPO: [Non-Fpo])
WARNING: Stack unwind information not available. Following frames may be wrong.
b9ef8c08 ba3605a7 00000000 00000000 00000000 regspy+0x1663
b9ef8c40 804ef095 85708778 00000000 806e4410 regspy+0x5a7
b9ef8c50 8057e70a 8520b7f8 85440158 8520b788 nt!IopfCallDriver+0x31 (FPO: [0,0,0])
b9ef8c64 8057f56d 85708778 8520b788 85440158 nt!IopSynchronousServiceTail+0x60 (FPO: [Non-Fpo])
b9ef8d00 805780c2 00000270 00000000 00000000 nt!IopXxxControlFile+0x5c5 (FPO: [Non-Fpo])
b9ef8d34 8054086c 00000270 00000000 00000000 nt!NtDeviceIoControlFile+0x2a (FPO: [Non-Fpo])
b9ef8d34 7c90eb94 00000270 00000000 00000000 nt!KiFastCallEntry+0xfc (FPO: [0,0] TrapFrame @ b9ef8d64)
012ffc0c 00000000 00000000 00000000 00000000 0x7c90eb94
start end module name
804d7000 806e2000 nt ntkrpamp.exe Wed Feb 28 02:38:53 2007 (45E53F9D)
806e2000 80702d00 hal halmacpi.dll Wed Aug 04 00:59:09 2004 (41107B2D)
b9385000 b93c5280 HTTP HTTP.sys Thu Mar 16 19:33:09 2006 (441A03C5)
b968c000 b96a0400 wdmaud wdmaud.sys Wed Jun 14 04:00:44 2006 (448FD03C)
ba061000 ba06fd80 sysaudio sysaudio.sys Wed Aug 04 01:15:54 2004 (41107F1A)
ba1e9000 ba23a480 srv srv.sys Mon Aug 14 05:34:39 2006 (44E051BF)
ba303000 ba32f400 mrxdav mrxdav.sys Wed Aug 04 01:00:49 2004 (41107B91)
ba360000 ba3626e0 regspy regspy.sys Fri Sep 23 09:08:29 2005 (43340C5D)
ba36c000 ba36f220 filespy filespy.sys Wed Jul 13 08:38:29 2005 (42D51955)
bade0000 bade3280 ndisuio ndisuio.sys Wed Aug 04 01:03:10 2004 (41107C1E)
bf800000 bf9c2180 win32k win32k.sys Thu Mar 08 07:47:34 2007 (45F013F6)
bf9c3000 bf9d4580 dxg dxg.sys Wed Aug 04 01:00:51 2004 (41107B93)
bf9d5000 bfe1eb00 nv4_disp nv4_disp.dll Wed Aug 16 18:16:53 2006 (44E3A765)
bffa0000 bffe5c00 ATMFD ATMFD.DLL Wed Aug 04 0256 2004 (411096C8)
f3c7c000 f3c95c00 dump_nvata dump_nvata.sys Wed Oct 18 19:31:35 2006 (4536C767)
f3ce6000 f3d54a00 mrxsmb mrxsmb.sys Fri May 05 04:41:42 2006 (445B1DD6)
f3d55000 f3d7fa00 rdbss rdbss.sys Fri May 05 04:47:55 2006 (445B1F4B)
f3d80000 f3da1d00 afd afd.sys Wed Aug 04 01:14:13 2004 (41107EB5)
f3da2000 f3dc2f00 ipnat ipnat.sys Wed Sep 29 17:28:36 2004 (415B3714)
f3dc3000 f3deac00 netbt netbt.sys Wed Aug 04 01:14:36 2004 (41107ECC)
f3deb000 f3e42d80 tcpip tcpip.sys Thu Apr 20 06:51:47 2006 (444775D3)
f3e43000 f3e55400 ipsec ipsec.sys Wed Aug 04 01:14:27 2004 (41107EC3)
f3ebf000 f3ec1900 Dxapi Dxapi.sys Fri Aug 17 15:53:19 2001 (3B7D843F)
f64eb000 f650e980 portcls portcls.sys Wed Aug 04 01:15:47 2004 (41107F13)
f650f000 f6621100 sthda sthda.sys Thu Jul 27 13:07:08 2006 (44C900CC)
f6c6e000 f6ca1200 update update.sys Wed Aug 04 00:58:32 2004 (41107B08)
f6cae000 f6cb1dc0 HPZipr12 HPZipr12.sys Fri Jan 03 07:25:03 2003 (3E158F2F)
f6cbe000 f6cc1b00 usbscan usbscan.sys Wed Aug 04 00:58:44 2004 (41107B14)
f6cca000 f6cfa100 rdpdr rdpdr.sys Wed Aug 04 01:01:10 2004 (41107BA6)
f6cfb000 f6d0be00 psched psched.sys Wed Aug 04 01:04:16 2004 (41107C60)
f6d0c000 f6d22680 ndiswan ndiswan.sys Wed Aug 04 01:14:30 2004 (41107EC6)
f6d23000 f6d49000 HDAudBus HDAudBus.sys Thu Aug 12 19:45:52 2004 (411C0F40)
f6d49000 f6d6b680 ks ks.sys Wed Aug 04 01:15:20 2004 (41107EF8)
f6d6c000 f6d8ee80 USBPORT USBPORT.SYS Wed Aug 04 01:08:34 2004 (41107D62)
f6d8f000 f6da2780 VIDEOPRT VIDEOPRT.SYS Wed Aug 04 01:07:04 2004 (41107D08)
f6da3000 f7169ba0 nv4_mini nv4_mini.sys Wed Aug 16 18:22:03 2006 (44E3A89B)
f7172000 f7174280 rasacd rasacd.sys Fri Aug 17 15:55:39 2001 (3B7D84CB)
f71b2000 f71cc580 Mup Mup.sys Wed Aug 04 01:15:20 2004 (41107EF8)
f71cd000 f71f9a80 NDIS NDIS.sys Wed Aug 04 01:14:27 2004 (41107EC3)
f71fa000 f7286400 Ntfs Ntfs.sys Fri Feb 09 05:10:31 2007 (45CC56A7)
f7287000 f729d780 KSecDD KSecDD.sys Wed Aug 04 00:59:45 2004 (41107B51)
f729e000 f72aff00 sr sr.sys Wed Aug 04 01:06:22 2004 (41107CDE)
f72b0000 f72cf780 fltmgr fltmgr.sys Mon Aug 21 04:14:57 2006 (44E97991)
f72d0000 f72e9c00 nvata nvata.sys Wed Oct 18 19:31:35 2006 (4536C767)
f72ea000 f7301480 atapi atapi.sys Wed Aug 04 00:59:41 2004 (41107B4D)
f7302000 f7327700 dmio dmio.sys Wed Aug 04 01:07:13 2004 (41107D11)
f7328000 f7346880 ftdisk ftdisk.sys Fri Aug 17 15:52:41 2001 (3B7D8419)
f7347000 f7357a80 pci pci.sys Wed Aug 04 01:07:45 2004 (41107D31)
f7358000 f7385d80 ACPI ACPI.sys Wed Aug 04 01:07:35 2004 (41107D27)
f7487000 f748fc00 isapnp isapnp.sys Fri Aug 17 15:58:01 2001 (3B7D8559)
f7497000 f74a1500 MountMgr MountMgr.sys Wed Aug 04 00:58:29 2004 (41107B05)
f74a7000 f74b3c80 VolSnap VolSnap.sys Wed Aug 04 01:00:14 2004 (41107B6E)
f74b7000 f74bfe00 disk disk.sys Wed Aug 04 00:59:53 2004 (41107B59)
f74c7000 f74d3200 CLASSPNP CLASSPNP.SYS Wed Aug 04 01:14:26 2004 (41107EC2)
f74d7000 f74dfb80 PxHelp20 PxHelp20.sys Wed Oct 18 12:33:53 2006 (45366581)
f7527000 f7536900 Cdfs Cdfs.SYS Wed Aug 04 01:14:09 2004 (41107EB1)
f75c7000 f75cfa00 processr processr.sys Wed Aug 04 00:59:14 2004 (41107B32)
f75d7000 f75e1380 imapi imapi.sys Wed Aug 04 01:00:12 2004 (41107B6C)
f75e7000 f75f3180 cdrom cdrom.sys Wed Aug 04 00:59:52 2004 (41107B58)
f75f7000 f7605080 redbook redbook.sys Wed Aug 04 00:59:34 2004 (41107B46)
f7607000 f7617000 bcm4sbxp bcm4sbxp.sys Tue Nov 21 06:25:43 2006 (4562F047)
f7617000 f7623880 rasl2tp rasl2tp.sys Wed Aug 04 01:14:21 2004 (41107EBD)
f7627000 f7631200 raspppoe raspppoe.sys Wed Aug 04 01:05:06 2004 (41107C92)
f7637000 f7642d00 raspptp raspptp.sys Wed Aug 04 01:14:26 2004 (41107EC2)
f7647000 f764f900 msgpc msgpc.sys Wed Aug 04 01:04:11 2004 (41107C5B)
f7657000 f7660f00 termdd termdd.sys Wed Aug 04 00:58:52 2004 (41107B1C)
f7677000 f7685b80 drmk drmk.sys Wed Aug 04 01:07:54 2004 (41107D3A)
f7687000 f7690480 NDProxy NDProxy.SYS Fri Aug 17 15:55:30 2001 (3B7D84C2)
f7697000 f76a5100 usbhub usbhub.sys Wed Aug 04 01:08:40 2004 (41107D68)
f76b7000 f76bf700 netbios netbios.sys Wed Aug 04 01:03:19 2004 (41107C27)
f76c7000 f76cf880 Fips Fips.SYS Fri Aug 17 20:31:49 2001 (3B7DC585)
f76d7000 f76dfd80 HIDCLASS HIDCLASS.SYS Wed Aug 04 01:08:18 2004 (41107D52)
f76e7000 f76ef700 wanarp wanarp.sys Wed Aug 04 01:04:57 2004 (41107C89)
f76f7000 f7703640 HPZid412 HPZid412.sys Fri Jan 03 07:25:01 2003 (3E158F2D)
f7707000 f770d200 PCIIDEX PCIIDEX.SYS Wed Aug 04 00:59:40 2004 (41107B4C)
f770f000 f7713900 PartMgr PartMgr.sys Fri Aug 17 20:32:23 2001 (3B7DC5A7)
f7717000 f771d080 szkg szkg.sys Tue Sep 05 15:19:03 2006 (44FDDBB7)
f7727000 f772e880 Npfs Npfs.SYS Wed Aug 04 01:00:38 2004 (41107B86)
f7737000 f773eb80 usbccgp usbccgp.sys Wed Aug 04 01:08:45 2004 (41107D6D)
f773f000 f7745500 usbprint usbprint.sys Wed Aug 04 01:01:23 2004 (41107BB3)
f7747000 f774c2c0 HPZius12 HPZius12.sys Wed Feb 05 00:40:52 2003 (3E40B1F4)
f7757000 f775b500 watchdog watchdog.sys Wed Aug 04 01:07:32 2004 (41107D24)
f781f000 f7823280 usbohci usbohci.sys Wed Aug 04 01:08:34 2004 (41107D62)
f7827000 f782d800 usbehci usbehci.sys Wed Aug 04 01:08:34 2004 (41107D62)
f782f000 f7836000 GEARAspiWDM GEARAspiWDM.sys Mon Aug 07 12:11:27 2006 (44D7743F)
f7837000 f783b880 TDI TDI.SYS Wed Aug 04 01:07:47 2004 (41107D33)
f783f000 f7843580 ptilink ptilink.sys Fri Aug 17 15:49:53 2001 (3B7D8371)
f7847000 f784b080 raspti raspti.sys Fri Aug 17 15:55:32 2001 (3B7D84C4)
f784f000 f7855000 kbdclass kbdclass.sys Wed Aug 04 00:58:32 2004 (41107B08)
f7857000 f785ca00 mouclass mouclass.sys Wed Aug 04 00:58:32 2004 (41107B08)
f787f000 f7885180 HIDPARSE HIDPARSE.SYS Wed Aug 04 01:08:15 2004 (41107D4F)
f7887000 f788c200 vga vga.sys Wed Aug 04 01:07:06 2004 (41107D0A)
f788f000 f7893a80 Msfs Msfs.SYS Wed Aug 04 01:00:37 2004 (41107B85)
f7897000 f789a000 BOOTVID BOOTVID.dll Fri Aug 17 15:49:09 2001 (3B7D8345)
f792b000 f792d580 hidusb hidusb.sys Fri Aug 17 16:02:16 2001 (3B7D8658)
f793b000 f793ea00 kbdhid kbdhid.sys Wed Aug 04 00:58:33 2004 (41107B09)
f7943000 f7945f80 mouhid mouhid.sys Fri Aug 17 15:47:57 2001 (3B7D82FD)
f795b000 f795d580 ndistapi ndistapi.sys Fri Aug 17 15:55:29 2001 (3B7D84C1)
f7977000 f797ac80 mssmbios mssmbios.sys Wed Aug 04 01:07:47 2004 (41107D33)
f7987000 f7988b80 kdcom kdcom.dll Fri Aug 17 15:49:10 2001 (3B7D8346)
f7989000 f798a100 WMILIB WMILIB.SYS Fri Aug 17 16:07:23 2001 (3B7D878B)
f798b000 f798c700 dmload dmload.sys Fri Aug 17 15:58:15 2001 (3B7D8567)
f79b3000 f79b4100 swenum swenum.sys Wed Aug 04 00:58:41 2004 (41107B11)
f79bf000 f79c0280 USBD USBD.SYS Fri Aug 17 16:02:58 2001 (3B7D8682)
f79c7000 f79c8f00 Fs_Rec Fs_Rec.SYS Fri Aug 17 15:49:37 2001 (3B7D8361)
f79c9000 f79ca080 Beep Beep.SYS Fri Aug 17 15:47:33 2001 (3B7D82E5)
f79cb000 f79cc080 mnmdd mnmdd.SYS Fri Aug 17 15:57:28 2001 (3B7D8538)
f79cd000 f79ce080 RDPCDD RDPCDD.sys Fri Aug 17 15:46:56 2001 (3B7D82C0)
f79d3000 f79d4100 dump_WMILIB dump_WMILIB.SYS Fri Aug 17 16:07:23 2001 (3B7D878B)
f7a4f000 f7a4fd00 pciide pciide.sys Fri Aug 17 15:51:49 2001 (3B7D83E5)
f7ae3000 f7ae3c00 audstub audstub.sys Fri Aug 17 15:59:40 2001 (3B7D85BC)
f7b0b000 f7b0bb80 Null Null.SYS Fri Aug 17 15:47:39 2001 (3B7D82EB)
f7b50000 f7b50d00 dxgthk dxgthk.sys Fri Aug 17 15:53:12 2001 (3B7D8438)

Unloaded modules:
b6b49000 b6b74000 kmixer.sys
Timestamp: unavailable (00000000)
Checksum: 00000000
b9616000 b9641000 kmixer.sys
Timestamp: unavailable (00000000)
Checksum: 00000000
f7ae9000 f7aea000 drmkaud.sys
Timestamp: unavailable (00000000)
Checksum: 00000000
ba3c0000 ba3cd000 DMusic.sys
Timestamp: unavailable (00000000)
Checksum: 00000000
ba380000 ba38e000 swmidi.sys
Timestamp: unavailable (00000000)
Checksum: 00000000
b9641000 b9664000 aec.sys
Timestamp: unavailable (00000000)
Checksum: 00000000
f799d000 f799f000 splitter.sys
Timestamp: unavailable (00000000)
Checksum: 00000000
f3efb000 f3f0b000 Serial.SYS
Timestamp: unavailable (00000000)
Checksum: 00000000
ba2c7000 ba2db000 Parport.SYS
Timestamp: unavailable (00000000)
Checksum: 00000000
f7176000 f717a000 kbdhid.sys
Timestamp: unavailable (00000000)
Checksum: 00000000
f76a7000 f76b4000 i8042prt.SYS
Timestamp: unavailable (00000000)
Checksum: 00000000
f7877000 f787c000 Cdaudio.SYS
Timestamp: unavailable (00000000)
Checksum: 00000000
f717a000 f717d000 Sfloppy.SYS
Timestamp: unavailable (00000000)
Checksum: 00000000
f786f000 f7874000 Flpydisk.SYS
Timestamp: unavailable (00000000)
Checksum: 00000000
f7867000 f786e000 Fdc.SYS
Timestamp: unavailable (00000000)
Checksum: 00000000
Closing open log file c:\debuglog.txt

here are the debugging results

You just built this computer? That's information that should have been in your opening post. So, did it do this from first power up? And note that many hardware devices need driver upgrades right out of the box.

this didnt do this when i first powered up, for what hardware should i get drivers for. i have downloaded all the urgent motherboard drivers.