Close Program/Task Manager
This is NOT a list of tasks/processes taken from Task Manager or the Close Program window (CTRL+ALT+DEL) but a list of startup applications, although you will find some of them listed via this method. Pressing CTRL+ALT+DEL identifies programs that are currently running - not necessarily at startup. For a list of tasks/processes you should try WinTasks 5 Standard/Professional from LIUtilities or the list at AnswersThatWork. Therefore, before ending a task/process via CTRL+ALT+DEL just because it has an "X" recommendation, please check whether it's in MSCONFIG or the registry first. An example would be "svchost.exe" - which doesn't appear in either under normal conditions but does via CTRL+ALT+DEL. If in doubt, don't do anything.

Operating System Differences
A number of entries are repeated due to the way that different operating systems display startup items. For example, WinMe lists "POPROXY.EXE" as "Norton eMail Protect" in both MSCONFIG and the registry whereas WinXP lists it as "Poproxy" in MSCONFIG and "Noeton eMail Protect" in the registry.

To avoid the list becoming too large, all VIRUSES are shown using the registry version which is common to all Windows versions.

Alternatively use your browsers search facility - Ctrl+F for IE users.

Key:

"Y" - Normally leave to run at start-up
"N" - Not required - typically infrequently used tasks that can be started manually if necessary
"U" - User's choice - depends whether a user deems it necessary
"X" - Definitely not required - typically viruses, spyware, adware and "resource hogs"
"?" - Unknown

Use your browsers search facility - Ctrl+F for IE users.

U	N2PTray	Net2fone.exe	An Internet telephony application. Needed only if you have an account at Net2Phone, Inc
N	NADaemon	NADAEMON.EXE	Program by NetActive which appears to be piggybacked onto some Nvidia graphics cards software. They seem to look after "digital rights management". One user reports disabling it has no detrimental affect - not required
N	Naggerrunkey	nagger.exe	Packard Bell Free Internet Signup screen
Y	Naimagent_service	EPOAgentnaimas32.exe	Networked version of McAfee VirusScan. Installs, configures and updates the software and DAT (virus definition) files on local computers from a network server. A resource hog but required for DAT updates and if disabled can also cause random freezes and error messages
Y	Naimagent_UI	EPOAgentnaimag32.exe	Workstation background program for Network Associates’ McAfee ePolicy Orchestrator - a network management tool for enforcing antivirus protection of the workstations using system policies. Works with both McAfee and Norton AntiVirus. NAIMAG32 and NAIMAS32 communicate with the ePolicy Orchestrator processes on the network fileserver to check for virus updates or for the need to perform a virus scan
Y	Naimagent_UI	naimag32.exe	Workstation background program for Network Associates’ McAfee ePolicy Orchestrator - a network management tool for enforcing antivirus protection of the workstations using system policies. Works with both McAfee and Norton AntiVirus. NAIMAG32 and NAIMAS32 communicate with the ePolicy Orchestrator processes on the network fileserver to check for virus updates or for the need to perform a virus scan
X	Name	Iexplorer0.exe	Added by the THREADSYS TROJAN!
X	NAP32	NAP32.exe	Premium rate adult content dialler
X	Narrator	******.exe [* = random char]	Transponder/VX2 related adware
X	Natal	Natal.scr	Added by the OPASERV.AE WORM!
X	NAV	RuxDLL32.exe	Added by the MAPSON.D WORM!
Y	NAV Agent	navapw32.exe	Norton Anti-Virus's background scanning process
X	nAv AGENT	N/A	Added by the RIOSYS MACRO! Note the lower-case "n" and "v" in the name as this is not the valid Norton AntiVirus entry of the same name - indeed it closes Norton AV processes
X	NAV Agent	systems.exe	Added by the TARNO.C TROJAN! Note - this is not the valid Norton Antivirus entry of the same name
X	NAV Agent	winsnav.vbs	Added by the ANPES WORM!
X	NAV Auto Protect	msfwe1.exe	Added by a variant of the RBOT WORM!
X	NAV Auto Protect	navprotect.exe	Added by a variant of the RBOT WORM!
X	NAV Auto Protect	dnsserv.exe	Added by a variant of the SDBOT WORM!
X	NAV Auto Protect	mcafee32.exe	Added by a variant of the SPYBOT WORM!
X	NAV Auto Update	Navautoupdate.exe	Added by a variant of the SPYBOT WORM!
X	NAV Auto Updates	csrssp.exe	Added by a variant of the SDBOT WORM!
X	NAV Auto Updates	navwindows.exe	Added by a variant of the SDBOT WORM!
N	NAV CfgWiz	cfgwiz.exe	Introduced with Norton Anti-Virus 2002, this is a real resource hog. Many NAV users will find they can live without loading it
N	NAV Configuration Wizard	cfgwiz.exe	Introduced with Norton Anti-Virus 2002, this is a real resource hog. Many NAV users will find they can live without loading it
U	NAV DefAlert	DefAlert.exe	Norton Anti-Virus Definitions Alert. Warns you if virus definitions are out of date. Leave enabled unless you manually update virus definitions on a regular basis
X	NAV Live Update	[path to worm]	Added by the DEBORMS.C WORM! Note - this is not a valid Norton Anti-Virus (NAV) function from Symantec
X	NAV Scan Service	NAVSCAN32.EXE	Added by the SDBOT.VG WORM!
X	NavAgent32	lasvr32.exe	Added by the FEMOT.D WORM!
X	NavAgent32	SCardSvr32.Exe	Added by the MOFEI.B WORM!
X	navapp	navapp.exe	NavExcel adware variant
Y	navapw32	navapw32.exe	Norton Anti-Virus's background scanning process
U	Naviscope	naviscope.exe	Naviscope is a multipurpose browser enhancement that can speed up Web searches, lock out cookies, examine HTML send/receive headers, provide single-click network diagnostics, and much more
X	NaviSearch	nls.exe	NaviSearch, eXact Advertising variant
X	navman_20	sysnav32.exe	Hijacker, possibly a CoolWebSearch variant
X	navp.exe	navp.exe	Added by the AGOBOT-OE WORM!
X	NavPass	NavPass.exe	Free system for gaining access to and downloading from adult content web-sites
X	NavScan	[filename]	Added by the OBSORB TROJAN!
X	NAVSCANNER32	NAVSCANNER32.EXE	Added by the RBOT.QC WORM!
X	NAVUpd	rundll32.exe navupd.dll, Startup	Added by the NAVU TROJAN!
N	NB Common Dialog Enhancements	COMDLGEX.EXE	Part of McAfee Nuts & Bolts. With Common Dialog Enhancements, you can add MRU list box to open dialogs
N	NB Start Menu	STARTM.EXE	Part of McAfee Nuts & Bolts. Provides the same control as MSCONFIG and can be used instead if you have N&B
N	NB Windows Patterns	WINDBKGND.EXE	Part of McAfee Nuts & Bolts. With Background Patterns, you can change background patterns of wizard and dialog windows
U	NBJ	NBJ.exe	Ahead Nero BackItUp backup program. Only required for if you have scheduled back-ups
U	NbkCtrl	NbkCtrl.exe	Scheduling engine of NovaSTOR Backup Service. Only required if scheduling is enabled and wanted - see here
X	NBT System alias	[path] repcale.exe [path] beird.exe	Added by a variant of the RANDON.AN WORM!
?	NCClient	N/A	??
N	NCD	ncd.exe	Norton Change Directory - from the DOS days that allows the user to change directories on their machine without typing the complete path
?	NCLAUNCH	NCLAUNCH.Exe	Part of SWF Studio from Northcode Inc - an extension to Flash. Bundled when you create a self-installing screen-saver on Win2K/XP. Is it required?
N	NCS_SS	Csinsm32.exe	Same as CleanSweep Smart Sweep-Internet Sweep
X	NDAv	csnss.exe	Added by the SERFLOG.C WORM!
X	NDAv	svhost.exe	Added by the SERFLOG.C WORM!
?	NDDEAGNT	NDDEAGNT.EXE	WinNT default process. Network Dynamic Data Exchange (DDE) Agent, handles requests for network DDE services
X	NDIS Adapter	ndis.exe	Added by the SDBOT.VF WORM!
X	NDIS Adapter	windows.exe	Added by the FORBOT-BR WORM!
X	NDIS Adapter	lsass2.exe	Added by a variant of the AGOBOT/GAOBOT WORM!
X	NDplDeamon	nstask32.exe	Added by the RANDEX.E WORM!
X	NDplDeamon	winlogin.exe	Added by the RANDEX.E WORM!
U	NDPS	DPMW32.EXE	Novell Distributed Printer Services - part of Novell's Netware Client and Groupwise products. Not required if you don't use this feature
X	NDrv	NDrv.exe	PurityScan/Clickspring adware
U	NDSTray	NDSTray.exe	ConfigFreeT Tray on a Toshiba laptop. Tray utility for their network switching application which permits switching network devices and settings with a click on the tray icon. While it is not required, for people who span multiple networks and want an easy way to go from wired to wireless and change addresses and other network settings, it's a must have
N	Necbar	Necbar.exe	Nec Assistant; Ark's Navigator, a graphical interface for NEC computers
Y	NECMFK	necmfk.exe	NEC wireless keyboard driver
U	Necutray	Necutray.exe	Driver for external USB storage devices (hard drives, flsh disks, etc)
?	neqprvfy.exe	neqprvfy.exe	Appears to be related to the downloading of some application - possibly verifying updates?
X	Nero.ma	***.exe [*** = 2 to 3 digits]	Added by the JONBARR.D WORM!
X	NeroAutoStartClient	NeroASM.exe	Added by the AGOBOT.VG WORM!
U	NeroCheck	nerocheck.exe	Associated with "Nero Burning Rom" CD writing software. Checks for driver issues
X	NeroCheck	regedit.exe	Added by the DOOMJUICE.B WORM! Note - this is not the valid Ahead Nero CD burning program. Also it is not the valid Windows registry editor which resides in C:Windows or C:Winnt wheras this version resides in C:WindowsSystem (Win9x/Me), C:WinntSystem32 (WinNT/2K) or C:WindowsSystem32 (WinXP)
U	NeroFilterCheck	NeroCheck.exe	Associated with "Nero Burning Rom" CD writing software. Checks for driver issues
N	NeroNETTrayIcon	NNServiceCtrl.exe	System tray access to NeroNET - Ahead Software's network-capable extension of their CD/DVD burning program. NeroNET allows a burner to be shared across a network
X	Net	WINREG.EXE	Added by the ASSASIN.D TROJAN!
U	Net Accelerator	NetAccelerator.exe	Rizal NetAccelerator - "Optimizing Dial-Up, Lan, Cable, DSL, and Satellite connections do you want to speed up your Internet access up to 200% - 300% ???". Only required if you find it helps improve your performance
U	Net Activity Diagram	nad.exe	Net Activity Diagram from MetaProducts. Monitors your computer internet activity. Available via Start -> Programs
N	Net-It Launcher	NILaunch.exe	Net-It - web publishing software
U	NetAccelerator	NetAccel.exe	NetAccelerator is a "software utility that optimizes your internet access up to 1200% faster!. NetAccelerator speeds all modems allowing you to download faster, browse faster, surf faster!. Only required if you find it helps improve your performance
X	NetAdm7	NETADM7.EXE	Added by the BANCOS.F TROJAN!
X	Netapi	Netapi.exe	Added by the NETDEVIL.14 TROJAN!
X	NetApp	winserv.exe	Added by the SHADOWTHIEF TROJAN!
X	netconfig	netconfig.exe	Added by the NETCONF TROJAN!
U	NetCruiser Dialer	NCDialer.exe	NetCruiser Dialer from NetCruiser Software. "An Internet dialer and connection monitor with features to launch applications when a connection is detected, dial and hangup at predefined times and automatic redialing of dropped connections"
X	netdaemon	netdaemon /v	Malware designed to "kill" a number of antispyware applications (SpyBot, Giant, SpyDoctor, SpySweeper, SpyHunter, Anvir, WinPatrol, and more)
X	netdll32	netdll32.exe	Added by the CRYPTER.A TROJAN!
X	netdllex	netdllex.Exe	Added by the CRYPTER.A TROJAN!
X	NetDy	VisualGuard.exe	Added by the NETSKY.N or NETSKY.W WORMS!
X	NETFP32.EXE	NETFP32.EXE	Added by the AGENT.CD TROJAN!
?	netfxupdate	netfxupdate.exe	Would appear to be a valid Microsoft .NET file (see here) but this suggest's it's a trojan?
?	NetFxUpdate_v1.0.3705	netfxupdate.exe	Would appear to be a valid Microsoft .NET file (see here) but this suggest's it's a trojan?
U	NetGuard	NetGuard.exe	FBM Software ZeroSpyware 2004 spyware detector and remover - real time monitor
U	Netlimiter	Netlimiter.exe	Netlimiter - "An internet traffic control tool to monitor applications which access the internet and actively control their internet traffic. Use it o set (download/upload) speed limits for applications or even single connection. NetLimiter also allows you to share your internet connection bandwidth among all applications running on your PC."
N	Netline User	netchk.exe	Netline supplies internet related products and services and this program identifies user ID and IP information. Found installed along with the Falcon 4 game, for example
X	NetLink	netlink32.exe	Added by the GAOBOT.WO WORM!
X	NetLogon	userint.exe	Added by the SDBOT-BC WORM!
X	NetManagerService	ntss.exe	Added by the BESTPICS.A TROJAN!
X	NetMeter	NetMeter.exe	NetRatings software by Opistat . "OpiStat measures Internet usage anonymously and surveys participants according to their profiles and online habits". This software has been reported to get downloaded and installed automatically after a Grokster install. It anonymously collects your use of the Internet protocols (sites visited, Web pages, advertisements seen, electronic commerce, streaming). To be avoided!
X	NetMon	netmon.exe	Added by the MIMAIL.M WORM!
U	netmsg	netmsg.exe	Net_Message is a small tool to send messages across the network, using the Windows Messenger Service, so there is no client install required to receive the messages. It has a number of other features as well
U	NetPatrol	winclient.exe	NetPatrol network monitoring software
X	netpc32.exe	netpc32.exe	Malware, probably CoolWebSearch parasite related
N	NetPerSec	NetPerSec.exe	NetPerSec - measures the real-time speed of your Internet connection
N	NetPumper	NetPumperIEProxy.exe	NetPumper download manager - bundles Cydoor and SaveNow adware, see here
X	NetReach	nrcheck.exe	Added by an unidentified VIRUS, WORM or TROJAN!
X	Netropa Internet Receiver	Netropa.exe	Netropa Internet Receiver. Shows a scrolling bar with the news. Major resource hog and flagged as spyware
U	NetRun	NetRun.exe	NetRun - will 'RUN' a 'List' of programs only when a internet connection is detected, and close/kill the same 'List' when the connection is lost
N	Netscape Messenger	NETSCAPE.EXE	In Netscape 6 (I know for sure with 6.2.1, maybe with 6.0) Netscape.exe is the main executable file for Netscape Navigator, Netscape Mail and News, and Netscape Messenger (the new name for the embedded AIM, no doubt to make it sound like Windows Messenger, the XP version of MSN Messenger). Basically, netscape.exe can be more than just Netscape Messenger, and Messenger can be more then just AIM in disguise, depending on the version of Netscape installed
N	Netscp6	Netscp6.exe	Netscape 6
X	netservices	recall.exe	Added by a variant of the SDBOT WORM!
U	NetShow Powerpoint Helper	NSPPTHLP.EXE	If disabled, user created fonts can no longer be seen by other programs
N	NetStat Live	Nsl.exe	AnalogX NetStat Live - TCP/IP protocol monitor which can be used to see your exact throughput on both incoming and outgoing data
X	netsv32	netsv32.exe	Added by the SDBOT-PX WORM!
U	NetTime	NETTIME.EXE	From a visitor - "This is the executable for NetTime. It is started from the registry when you check the box to start at startup. NetTime allows you to synchronize your computers' clock with a server on your local net or the internet using any of several protocols, e.g. NTP."
U	NetTurbo	netturbo.exe	NetTurbo from SharewareOnline.com. "Accelerate Your Internet Connections by up to 600%". If you find it helps your connectivity leave it enabled
X	Netunit32	wunit32.exe	Added by an unidentified WORM or TROJAN!
X	NetWatch32	netwatch.exe	Added by the MIMAIL.C WORM!
N	Netword Agent	nwant33.exe	An interesting browser utility that allows you to navigate by typing a single word or phrase (a "NetWord") related to what you're looking for into your browser's location field. It also puts an icon in the system tray icon that is a circle with the letter N in the center to access the menu faster. Available via Start -> Programs