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	Y!TunnelPro	YTunnelPro.exe	Spam, bot and ad blocker for Yahoo! Messenger from Digital Asphyxia
U	Y!TunnelPro	YTPro.exe	Spam, bot and ad blocker for Yahoo! Messenger from Digital Asphyxia
X	yahoo groups	upgrdmgr.exe	Added by a variant of the RBOT WORM!
?	Yahoo HP Reminder 1.1	yr.exe	??
X	Yahoo Instant Messengar	YahooMsgr.exe	Added by the SDBOT.GEN TROJAN!
X	Yahoo Messenger	Yahoomsg.exe	Added by an unidentified WORM or TROJAN!
X	Yahoo Messenger	YPager.exe	Added by the RBOT-QO WORM!
X	Yahoo Update	Yahoo.exe	Added by the YAHOO! TROJAN!
N	Yahoo! Pager	ypager.exe	Yahoo! Messenger allows you to send instant messages. Available via Start -> Programs
X	YahooStock	Prmvr.exe	Adtomi adware
X	YahooStock	ystckAO32.exe	Adtomi adware
X	yahoo_toolbar lptt01	yahoo_toolbar.exe	Variant of the RapidBlaster parasite (in a "yahoo_toolbar" folder in Program Files). It is not recommended you manually uninstall RapidBlaster but use RapidBlaster Killer - see here
X	yahoo_toolbar ml097e	yahoo_toolbar.exe	Variant of the RapidBlaster parasite (in a "yahoo_toolbar" folder in Program Files). It is not recommended you manually uninstall RapidBlaster but use RapidBlaster Killer - see here
N	YAMAHA DS-XG Launcher	dslaunch.exe	System Tray access for the features of the Yamaha DS-XG soundcard unless you regularly change set-ups
N	Yankee Clipper III	YankClip.exe	Yankee Clipper III - 'A super powerful Windows clipboard extender/memory - now in its third generation. Handles Pictures, Richtext, URLS, etc - any size. Features printing, drag and drop, optional permanent storage of clippings. Familiar "Outlook" interface'. Freeware
N	YBrowser	ybrwicon.exe	SBC Yahoo! Browser system tray icon
X	yeahdude.exe	hallowelt.exe	Added by the GAOBOT.RS or GAOBOT.SA WORMS!
U	You've Got Pictures Screensaver	ygpsstra.exe	AOL You've Got Pictures® Screensaver
?	YOW tuner	WatchPNM.exe	??
N	ypager	ypager.exe	Yahoo! Messenger allows you to send instant messages. Available via Start -> Programs
U	YPC	ypc.exe	Yahoo Parental controls - "Let you decide what type of sites and Yahoo! services your kids can access"
Y	YTrayMagic Lite 1	YTRAYMAGIC.EXE	YTrayMagic from YoconSoft automatically restores your tray icons after an Explorer(the windows shell) crash. Leave to run at startup since only those icons that are in the taskbar after YTrayMagic has initialized will be restored
X	ywzizdon	ywzizdon.exe	Free_Scratch_Cards foistware
X	yyyyyyyy	[path to trojan]	Added by the MUMUBOY.B TROJAN!
X	yz.exe	yz.exe	Added by the VARDO TROJAN!
X	YZH.SYS	YZH.exe	Added by the SOPHILY VIRUS!
U	z-WrDialer	WrDialer.exe	WinPoet DSL dialer
X	ZaCker	[filename].PIF	Added by the HOLAR.A WORM!
X	Zacker	Zacker.exe	Added by the GEMEL WORM!
X	zango	zango.exe	180Solutions/N-Case adware variant
Y	Zapro	Zapro.exe	Firewall program from Zonelabs - paid for version
U	zBrowser Launcher	iTouch.exe	For a Logitech internet keyboard - loads the software for the shortcut keys on the keyboard. Also used to display your keyboard LEDs on-screen to indicate Caps Lock, etc if it doesn't have them
U	zBrowser Launcher	Commandr.exe	For a Logitech internet keyboard - loads the software for the shortcut keys on the keyboard. Also used to display your keyboard LEDs on-screen to indicate Caps Lock, etc if it doesn't have them
?	zcb	zcb.exe	??
X	zcproo	qssstiej.exe	Possible homepage hijacker installing a toolbar: http://tdko.com/ ,Lop.com in disguise. see this thread
N	zdnet	kontiki.exe	Kontiki Delivery Manager - Windows-based client software that enables secure delivery of content to users' desktops
N	Zebus	msdc32.exe	Runs a HTML tutorial on the Zebus web-site
X	Zen.A	[path to trojan]	Added by the ZOOMEN-A TROJAN!
X	Zenet	rundll32 CNBabe.dll, DllStartup	CommonName Toolbar spyware. To uninstall see here
Y	ZENRC	zenrc32.exe	The main component of Novell's ZenWorks - "Complete End-to-End Directory-enabled Network Management". Leave well alone
Y	ZENRC Tray Icon	zentray.exe	Part of Novell's ZenWorks - "Complete End-to-End Directory-enabled Network Management". Best left alone
Y	ZENworks Imaging Service	ZISWin.exe	Imaging Agent. Part of Novell's ZenWorks - "Complete End-to-End Directory-enabled Network Management"
U	ZeroAds	0	ZeroAds - culls ads, cookies and pop-ups. Tells ZeroAds not to run at startup - needed to start it manually
U	ZeroAds	LAS0Ads.exe	ZeroAds - culls ads, cookies and pop-ups. Required for the cookie interception to work
U	ZeroSpyware	ZeroSpyware.exe	FBM Software ZeroSpyware 2004 spyware detector and remover
X	zervpack2	update2.exe	Added by the SDBOT.WD WORM!
?	ZGNUBI	ZGNUBI.exe	??
X	ZIBMACC	rundll.exe ZIBMACC.INF	ZIBMACC.INF is an IBM file that is only loaded and installed under a recovery operation. The file is a support file for IBM access to the system if needed. You may delete this file. This is as from IBM Technical Support (USA - 800-887-7435)
U	ZingSpooler	ZingSpooler.exe	Was used for a drag and drop program to upload pictures to www.zing.com but Zing has gone out of business. Now used for Sony ImageStation's upload photos to online albums
N	Zinio DLM	ZDLM.EXE	Zinio - used to read magazines in digital rather than paper format
X	Zip Driver Loader	ZipLoader32.exe	Added by the OBLIVION TROJAN! This executable is one of the most common but there are more
X	Zip Driver Loader	msload32.exe	Added by the OBLIVION TROJAN! This executable is one of the most common but there are more
U	ZipDisk Icons	IMGICON.EXE	Displays Iomega icons in Explorer/My Computer, ejects Zip disks on shutdown and displays a special delete confirmation box when deleting files on an Iomega drive. Available via Start -> Programs. If you disable it remember to eject disks first before powering the drive down - hence the "U" recommendation. Note - FreeCell may not run with ImgIcon running
N	ZipGenius Clean	zg.exe	ZipGenius file compression utility
X	ziphelp	ziphelp.exe	CoolWebSearch parasite related
N	ZipMagic	zm32.exe	Zip utility by Ontrack. Preloading ZipMagic allows you to access files within a zip archive without unzipping them first
Y	zlclient	zlclient.exe	Firewall program from Zonelabs. Pro version inlcudes other online security options
U	ZLH	ZLH.EXE	System Tray icon for Norman Antivirus
X	Zonavirus	0	Added by the KITRO.D (or ARGEN.A) WORM!
X	Zone Alarm	vsmon.exe	Added by the RBOT.BO WORM! If this was the ZoneAlarm firewall the name column would be TrueVector
Y	Zone Labs Client	zlclient.exe	Firewall program from Zonelabs. Pro version inlcudes other online security options
X	Zone Labs Client Ex	svchost.exe	Added by the NETSKY.F WORM! Note - this is not the legitimate svchost.exe process which should NOT appear in Msconfig/Startup!
X	Zone system	szchost.exe	Added by the MULTIDR-AC TROJAN!
Y	ZoneAlarm	zonealarm.exe	Firewall program from Zonelabs - free version
X	zonealarm	[random filename]	Added by an unidentified VIRUS, WORM or TROJAN! The only exception is if you have an older version of the ZoneAlarm firewall running
X	Zonealarm	Removeme.exe	Added by the FORBOT-BG WORM!
Y	ZoneAlarm Plus	zaplus.exe	Firewall program from Zonelabs - paid for version
Y	ZoneAlarm Pro	Zapro.exe	Firewall program from Zonelabs - paid for version
U	Zoom	zoom.exe	Zoom - speeds up Windows startup and manages startup applications
?	ZoomingHook	ZoomingHook.exe	Related to the Toshiba Zooming Utility for Tablet PC. What does it do and is it required?
Y	ZPOINT32	ZPOINT32.exe	USB graphics/writing tablet driver
X	zSearch	Zstb.exe	TotalVelocity zSearch parasite
U	zSPGuard	Spguard.exe	"StartPage Guard (SPG) protects your PC from cyberscam, by detecting and preventing any unauthorized changes to your internet browser's Start and Search pages. It is also capable of removing automatically most of known 'invaders'."
X	ZtgServerSwitch	server.vbs	ZTGServerswitch is part of Sony's Vaio support agent - designed by Support.com. Not required if the user does not wish to use the Vaio support agent and regarded as spyware
X	Zupdate	Zupdate.exe	B3d Projector foistware - periodically trys to access the internet. (1) Uninstall it via Start -> Settings -> Control Panel -> Add/Remove Programs. (2) Remove the BDEsecureinstall.exe if still present in C:\Windows\System. (3) Disable and ideally delete it from the registry. (4) Remove the "BDE" directory and all its contents
X	zzb	zzb.exe	IAGold adware downloader
X	zzb	zzb.exe	IAGold adware downloader
X	zzgshp	gshp.vbs	Homepage hi-jacker that re-defines your IE or Netscape start page
X	zztp	svchost.exe	Added by the TANNICK.B TROJAN! Note - this is not the legitimate svchost.exe process which should NOT appear in Msconfig/Startup!
?	zzz-hpi-boot	hpi-boot.exe	Associated with HP Photosmart printers
?	zzzCamlnSuitelll	setup.exe 46***	??
?	zzzhpsetup	setup.exe	??
X	[default]	DrWatson32.exe	Added by the DREMN TROJAN!
X	[Ephemeral 2.x] by TreeHugger,	[path to worm]	Added by the LEMOOR.A WORM! where "x" represents 3 or 4
X	[executed file name]	App.exe	Added by the WAXPOW WORM!
X	[executed file name]	Regsrv32.com	Added by the SOUTHGHOST WORM!
X	[random 12 digit number]	avifile5.exe	Adsrv.com/IeDriver adware variant
X	[random 12 digit number]	bootvid4.exe	Adsrv.com/IeDriver adware variant
X	[random 12 digit number]	browser8.exe	Adsrv.com/IeDriver adware variant
X	[random 12 digit number]	atitvo32.exe	Adsrv.com/IeDriver adware variant
X	[random 12 digit number]	autodisc.exe	Adsrv.com/IeDriver adware variant
X	[random 12 digit number]	cabview1.exe	Adsrv.com/IeDriver adware variant
X	[random 12 digit number]	advpack1.exe	Adsrv.com/IeDriver adware variant
X	[random 12 digit number]	batmeter.exe	Adsrv.com/IeDriver adware variant
X	[random 12 digit number]	bidispl2.exe	Adsrv.com/IeDriver adware variant
X	[random name]	Svchosts.exe	Added by the SDBOT.N TROJAN!
X	[random name]	wincpu.exe	Added by an unidentified VIRUS, WORM or TROJAN!
N	[System Mechanic Professional Update [Incinerator.dll]	REREG: [path] Incinerator.dll	System_Mechanic's "Incinerator" feature securely deletes files and folders from your PC so they can never be recovered again
X	[various names]	elf.exe	Elf is a hacker program, tied to a trojan server
X	[various names]	crsrs.exe	Added by the FORBOT-AK WORM!
X	[various names]	Windows32.exe	Added by any of a number of WORM or TROJAN variants
X	[various names]	bling.exe	Added by the RBOT-NI WORM!
X	[various names]	mediaplayer32.exe	Added by a variant of the RBOT WORM!
X	[various names]	winlogon32.exe	Added by an unidentified WORM or TROJAN!
X	[various names]	svchostss.exe	Added by a variant of the RBOT WORM!
X	[various names]	win32snd.exe	Added by the RBOT-DQ WORM!
X	[various names]	shch.exe	Premium rate adult content dialler
X	[various names]	PasswdMon.exe	TROJAN! - part of Wareout, malware masquerading as a spyware and dialer remover, see here
X	[various names]	runload32.exe	TROJAN! - part of Wareout, malware masquerading as a spyware and dialer remover, see here
X	[]	spolsvr2.exe	Added by the EVILSOCK.10 TROJAN!
X	[]	iexpl0res.exe	Added by an unidentified WORM or TROJAN!
X	[]	winbas12.exe	Adware, probably CoolWebSearch parasite related - recognized by Kaspersky antivirus as TrojanDownloader.Win32.VB.du
X	\IEService.exe	IEService.exe	FastFind parasite variant
X	\Pribi.exe	Pribi.exe	FastFind parasite variant
X	^`d}qZxu	~`d}qzxu3zYF	Added by the GAOBOT.GEN!POLY WORM!
U	_AntiSpyware	MssCli.exe	McAfee AntiSpyware
X	_Hazafibb	[path to file]	Added by the ZAFI.B WORM!
X	_svchost.con	svchost.com	Added by the ERKEZ.C WORM!
U	_winadm	winadm.exe	Parents Friend - "Log any activity and protect programs with a password. Further more you can lock the pc any hour in the week you want with the main password. You can also give users allowed programs in their program-lists and you can limit the maximal daily hours and maximal weekly hours user spend on the PC"
X	_winsystem.sys	smss.exe	Added by the SOBER.K WORM! Note - this is not the legitimate Smss.exe system file should normally NOT figure in Msconfig/Startup!
X	_x-Finder	_x-Finder.exe	Disconnects and redials an ISP modem to an adult content site
U	{0228e555-4f9c-4e35-a3ec-b109a192b4c2}	gnotify.exe	Google Gmail_notifier. Alerts you when you have new Gmail messages
X	{12EE7A5E-0674-42f9-A76B-000000004D00}	rundll32.exe [path] stlb2.dll, DllRunMain	BrowserAid/Startium parasite
X	{2CF0B992-5EEB-4143-99C0-5297EF71F444}	rundll32.exe stlbdist.dll, DllRunMain	BrowserAid/Startium parasite
X	{2CF0B992-5EEB-4143-99C2-5297EF71F44B}	rundll32.exe stlbupdt.DLL, DllRunMain	BrowserAid/Startium parasite
X	{357AA41A-B7A8-4632-A27D-5B980B25CF43}	[path to svchost.exe]	Added by the SMALL-AQ TROJAN!
X	®Windows Update	svchosts.exe	Added by the FRUCTA TROJAN!