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.

?	M Player Post Installer	postinstallm.exe	??
X	M-soft Office	M-soft Office.hta	HTA file which creates an executable on the hard drive which subsequently proceeds to download files from a malware site!
X	M1cr0s0ft S3rcurity	systemconfig.exe	Added by the RBOT.BKB WORM!
X	M1cr0s0ft Upd4t4zS	update32.exe	Added by the RBOT-MI WORM!
X	m32info	m32info.exe	Added by the CRYPTER.A TROJAN!
N	M3Tray	m3tray.exe	Movielink - internet movie rental System Tray access
X	Macfee Security Patch	Mpfsheild.exe	Added by the RBOT-NP WORM!
U	Machine Debug Manager	mdm.exe	Used by developers for debugging. Those who have encountered it have unchecked it with no degradation in performance. May cause your computer to "hang" if you have MS Visual Studio installed and this disabled because it appears to take over error handling - hence the U recommendatioon. Can also be listed as MDM7. See here to disable
N	MacLic	MacLic.exe	Part of Conversions Plus from DataViz - allowing PC and MAC owners to share disks
N	MacName	MacName.exe	Part of Conversions Plus from DataViz - allowing PC and MAC owners to share disks
Y	MAD.EXE	MAD.EXE	MAD.exe is the MS Exchange 5.5 System Attendant and can also consume a large amount of resources - resolved by the latest Exchange 5.5 Service Pack. Also part of Exchange 2000 Server but does it have the same problems?. Apparently you need to leave this running but is it needed at start-up?
N	MadExe	LaunchRA.exe	Dell Resolution Assistant
U	MagicDsk	MAGICDSK.EXE	Magic DeskTop is a small and novel utility which will allow you the option of hiding or showing your desktop icons
N	Magitime	Magitime.exe	Magitime - connection tracking utility which monitors online time, expense, data transfer
?	Mail.com	mcalert.exe	Mail.com - free web-mail service. Does mcalert.exe notify you when new mail has arrived?
U	MailBell	mailbell.exe	MailBell e-mail notification tool that will notify you about new messages arrived to your mailbox. Works with both POP3 mailboxes and web-mail based systems. You should be able to set your mail system to check all accounts at regular intervals anyway if you prefer (in Outlook for instance)
U	Mailbox Verifier	mboxvrfy.exe	Mailbox Verifier (MV) is free software that will notify you about new messages arrived to your mailbox. Only works with POP3 mailboxes (not web-mail based systems). You should be able to set your mail system to check all accounts at regular intervals anyway if you prefer (in Outlook for instance)
Y	MailScan Dispatcher	Launch.exe	MailScan Dispatcher splits each e-mail message into various components such as the header, body and attachment. Compressed formats (ZIP, ARJ, etc.) are scanned for viruses and cleaned
X	Mail_Check	Mail_Check.exe	Added by the PANOIL.C WORM!
U	MAIN	main.exe	SpyCop surveillance software detection - checks to see when your machine was last scanned and if it was more than a week asks if you want to scan
?	Main Executable (HP)	HP05T0R5.exe	HP (Hewlett-Packard) related. Maybe related to printers. Now - what does it do?
X	main16	main16.exe	Added by the CRYPTER.A TROJAN!
X	main32	main32.exe	Added by the CRYPTER.A TROJAN!
X	mainviewex	mainviewex.exe	Added by the GEMA.D TROJAN!
N	Mania Win Restore	RESWIN.EXE	Pinball Mania for Windows from 21st Century Entertainment LTD (1995). Runs briefly at start-up then terminates. Available via Start -> Programs
X	Mantis	[filename]	Added by the MANTIBE VIRUS!
X	MapiDrv	mpisvc.exe	Added by the MIPSIV TROJAN!
X	mapisvc32	mapisvc32.exe	Added by the KX VIRUS and also recognised by Symantec as FPAI adware
N	masqform.exe	masqform.exe	PureEdge Viewer 6.0, reportedly associated with viewing and text editing US Air Force electronic forms
N	Mass storage check registry	rundll32.exe MSDServ.dll, check registry	Used with a USB based smartmedia card reader
U	Master Volume Spy	MASTERVOLUMESPY.EXE	Volume control for the Gateway Destination "DestiVu" media interface
U	Matador	mlfbuddy.exe	MailFrontier - anti-spam application
U	Matador	mantispm.exe	MailFrontier Desktop (Matador) email spam blocker software
X	MatrixScreen	[filename]	Added by the MATRIXSCREEN TROJAN!
X	MatrixScreenSaver	mss.exe	Malware, see here
N	Matrox Color Control	hgcctl95.exe	For Matrox video cards. Quick access to changing colors
N	Matrox Control Center	mgactrl.exe	For Matrox video cards. Quick access to settings
N	Matrox Diagnostic	mgadiag.exe	For Matrox video cards. Quick access to diagnostics
N	Matrox Powerdesk	PDesk.exe	For Matrox video cards. Quick access to tweak your card to your liking
N	Matrox PowerDesk 8	Matrox.PowerDesk.exe /silent	For Matrox video cards. Quick access to tweak your card to your liking
N	Matrox QuickDesk	mgaqdesk.exe	For Matrox video cards. Quick access to tweak your card to your liking
X	MaxAlerts	max.exe	Bonzi MaxALERT - spyware
Y	MaxtorCombo	ComboButton.exe	Required to be able to use the Maxtor OneTouch button on your external Maxtor harddrive. It is used to start up backup software (Retrospect)
U	MaxtorReg	AUTOREG.EXE	Part of SYSagent - small utility for retrieving all the hardware and software information required by anyone administering a machine and/or the network it's a part of
U	MBM 4	MBM4.exe	Motherboard Monitor 4 - only needed if you overclock your system and want to keep a check on system temperatures/voltages/etc. Available via Start -> Programs
U	MBM 5	MBM5.exe	Motherboard Monitor 5 - only needed if you overclock your system and want to keep a check on system temperatures/voltages/etc. Available via Start -> Programs
U	MBProbe	mbrpobe.exe	MBProbe - only needed if you overclock your system and want to keep a check on system temperatures/voltages/etc. Available via Start -> Programs
X	MC	wintrims.exe	Added by the WINTRIM TROJAN!
X	Mcafee Anti Scan	NortonScn.exe	Added by a variant of the RBOT WORM!
X	Mcafee Antivirus Monitoring System32mn	VSStatmn32.exe	Added by a variant of the RBOT WORM!
Y	McAfee Firewall	CPD.EXE	Firewall bundled with McAfee VirusScan 6.*. Can also be listed as CPD_EXE
N	McAfee Guardian	CMGRDIAN.EXE	McAfee's QuickClean, an offline version of the one in their online Clinic. Normally run offline and not needed. Incidentally, incorporates more cleanup programs than the likes of WinOptimizer and System Mechanic
N	McAfee QuickClean Imonitor	Plguni.exe	McAfee QuickClean 3.0 - removes internet clutter and unwanted programs
X	McAfee Windows Protection	mcafee32.exe	Added by a variant of the SPYBOT WORM!
N	McAfee Winguage	??	Part of McAfee Nuts & Bolts. "WinGuage is a dynamic reporting tool that constantly monitors your use of Windows and your applications, to alert you to potential problems before they become serious". Resource hog. Available via Start -> Programs
U	McAfee.InstantUpdate.Monitor	RuLaunch.exe	Instant Updater for McAfee's VirusScan, Internet Security, Quick Clean, Uninstaller and Firewall products. In the case of VirusScan leave it enabled unless you update manually on a regular basis
Y	McAfeeUpdaterUI	UpdaterUI.exe	Associated with McAfee Enterprise 7.0.0. - background process
Y	McAfeeVirusScanService	Avsynmgr.exe	From McAfee VirusScan version 5.x. Runs VirusScan System Tray (Vsstat.exe), WebScanX (Webscanx.exe), VirusScan System Scan (Vshwin32.exe) and VirusScan Console (Avconsol.exe) under one application
Y	McAfeeWebscanX	WebScanX.exe	From McAfee VirusScan up to version 4.x. Provides functionality for VShield Download Scan and Internet Filter modules. Enables internet scanning. Guards against malicious ActiveX programs, etc
X	Mcaffe Antivirus	Mcafeescn.exe	Added by a variant of the SPYBOT WORM!
U	McAgentExe	mcagent.exe	From McAfee VirusScan On-line. The Agent is a red M icon that appears in the Windows system tray or Notification Area (if you're running Windows XP). If you don't see the agent icon, VirusScan Online may not be installed
?	Mcappins.exe	mcappins.exe	McAfee Application Installer. What does it do and is it required?
N	MChanger	MChanger.exe	Media Changer - utility that allows you to change wallpapers, sounds, themes, etc
?	McRegWiz	mcregwiz.exe	McAfee antivirus related. What does it do and is it required?
U	McUpdateExe	mcupdate.exe	From McAfee VirusScan On-line. Automatically updates your virus definitions. Leave enabled unless you regularly update these definitions
Y	McVsRte	mcusrt.exe	Part of McAfee's SecurityCenter. Must remain checked but one  user reports Windows glitches with no response from McAfee as to why
Y	mcvsshld	mcvsshld.exe	McAfee VirusScan On-line. See also the McAgentExe entry
X	MD IE Plugin	md.exe	Adult content dialler
X	MD IE Plugin	winy.exe	Adware
N	mdac_runonce	runonce.exe	Associated with MS Data Access Components (MDAC). Sometimes left over after installation - not required. NOTE :- don't delete "runonce.exe".
X	mdetect	[path to trojan]	Added by the SPABOT TROJAN!
X	Mdm	Mdm.vbs	Added by the WHITEHO VIRUS or TRAPPY WORM!
X	mdm	mdm.exe	Added by the LYDRA-F TROJAN! Note - this is not the valid Machine Debug Manager which shares the same filename
U	MDM7	mdm.exe	Used by developers for debugging. Those who have encountered it have unchecked it with no degradation in performance. May cause your computer to "hang" if you have MS Visual Studio installed and this disabled because it appears to take over error handling - hence the U recommendatioon. Can also be listed as Machine Debug Manager. See here to disable
X	Mdmdll	mdmdll.exe	Added by the CRYPTER TROJAN!
X	Mdmdll32	mdmdll32.exe	Added by a variant of the CRYPTER.C TROJAN!
X	MDN	MDNS.exe	Added by the SPYBOT.JPB WORM!
X	MDN	MDNZ.exe	Added by the RBOT.AQD WORM!
X	mdwmdmsp	mdwmdmsp.exe	Adware - recognized by Kaspersky antivirus and others as TrojanDownloader.Win32.Agent.am
N	MECA	Meca.exe	Meca instant messenging client
X	Media Access	MediaAccK.exe	Windupdates adware variant
X	Media Load	msn32.exe	Added by a unidentified WORM or TROJAN!
U	Media Manager Indexer	AIRSVCU.EXE	Part of MS Visual InterDev, Media Manager is an easy media file management system that works in conjunction with Windows Explorer. The Media Manager Indexer is a program that indexes all the information about your media files and puts it into a database. For more information see here
X	Media Pass	MediaPassK.exe	Windupdates adware variant
X	Media Player	media.exe	Added by the FLDMEDIA-A TROJAN!
X	Media Player	wmplayer.exe	Added by the AGOBOT-BM WORM!
X	Media Plug x.1.2	msdm.exe	Added by the MULDROP.352 VIRUS!
X	Media Service	msn64.exe	Added by the SPYBOT.EV WORM!
X	Media service	msnmsgxr.exe	Added by the SDBOT.TF WORM!
X	Media service	SYSTEM64.EXE	Added by the RBOT.QV WORM!
N	MediaFace Integration	Sethook.exe	Fellowes Neato™ cd label design software. "Launch NEATO's MediaFACE II label making software directly from the productname toolbar"
U	Mediafour Mac Volume Notifications	Macvntfy.exe	Mediafour Xplay - allows you to use an Apple iPod digital music player with a PC running Windows. If not used regularily start manually before connecting the iPod
U	Mediafour XPlay Tray Notification Icon	Xptryicn.exe	Mediafour Xplay - allows you to use an Apple iPod digital music player with a PC running Windows. If not used regularily start manually before connecting the iPod
U	MediaKey	MediaKey.exe	Multimedia keyboard manager. Required if you use the multimedia keys
X	MediaLoads	dw.exe	Medialoads is advertising software - running DownloadWare as its executable. Installed as a bundle with Kazaa Media Desktop. See here for more information
X	MediaLoads Installer	dw.exe	Medialoads is advertising software - running DownloadWare as its executable. Installed as a bundle with Kazaa Media Desktop. See here for more information
N	MediaMonitor	Mediam~1.exe	Installed by Smartdisk MVP CD burning software. Software will work fine without it
X	mediamotor.exe	mmups.exe	Roimoi/Media-Motor adware
X	MediaPath	Proyecto1.exe	Added by the GRUEL WORM!
X	MediaPath	Root.exe	Added by the GRUEL WORM!
N	MediaRing Talk	mrtalk.exe	Media Ring Talk, voice recognition software, Resource hog. Available via Start -> Programs
X	media_manager	mediaman.exe	Mini-Player,  IMESH related foistware, see here
X	media_stub	stub.exe	Mini-Player,  IMESH related foistware, see here
X	MemConfig	SetupIE.com	Added by the TAPLAK WORM!
U	MemoKit	MK.EXE	Memory optimizer. It loads from startup group and it goes off as soon as the program (memokit.exe) is loaded in the System Tray. Mk.exe does not run while the memokit.exe is running. Probably loads a flash screen at startup and shutdown that stays on screen less than 5 seconds and gives you a button to push to purchase the full version. MS professionals recommend not using memory managers with Win98/SE/ME. See this article and make up your own mind
X	Memory Check	memore.exe	Added by the KILLAV.C TROJAN!
N	Memory Stick Monitor	MSTAT.exe	Used with the Sony floppy disk adapter for memory sticks, showing if there is a stick in the computer
U	Memory Stick Monitor	MSstat.exe	Sony/SmartDisk memorystick-floppydisk-adapter software - allows you to read memorysticks in a normal floppydrive
X	Memory Watcher	MemoryWatcher.exe	MemoryWatcher spyware
U	Memory+	tfimemsr.exe	Memory optimizer. MS professionals recommend not using memory managers with Win98/SE/ME. See this article and make up your own mind
X	MemoryMeter	MemoryMeter.exe	Autoinstalling spyware by Total Velocity
X	MEMreaload	MEMreaload.exe	Added by the LAZAR TROJAN!
N	MemScanner	MemScanner.exe	SpyHunter - spyware remover of somewhat dubious repute, see note
U	MemTurbo	memturbo.exe	MemTurbo memory optimizer. MS professionals recommend not using memory managers with Win98/SE/ME. See this article and make up your own mind
N	MenuSnap	MenuSnap.exe	MenuSnap from Rietta Solutions. Utility that re-orders your Start Menu items alphabetically. You may not want this utility if you're able to do this manually by selecting Start -> Programs and right-clicking and choosing "Sort by Name" if availabe
X	Message Queuing	msmqs.exe	Added by the FREEFORS TROJAN!
N	MessagerStarter Freeserve	StartMessager.exe	Freeserve Messenger
U	Message_Blocker	messageblock.exe	Message Blocker - "prevents Outlook Express from loading images or other content from the internet without confirmation, as well as executing scripts when displaying a formatted email message"
X	Messanger	trillian.exe	Added by a variant of the AGOBOT/GAOBOT WORM!
X	Messenger	messenger.exe	Added by the KUTEX TROJAN!
X	Messenger Block	msngrblock.exe	Added by the PATOO WORM!
X	Messenger start-up	Msgran.exe	Added by the GRAMOS WORM!
X	Messenger6	command.pif	Added by the INZAE.B WORM!
U	MessengerDiscovery	MessengerDiscovery.exe	MessengerDiscovery is a MSN Messenger add-on - adding over 70 new features
N	MessengerPlus	MsgPlus.exe	MessengerPlus - third party MSN Messenger extension that adds a number of useful features. Bundles the hard to remove C2Media LOP adware. The software does offer you a choice during setup - make sure to install MessengerPlus WITHOUT that "sponsor program"!
N	MessengerPlus2	MsgPlus.exe	MessengerPlus - third party MSN Messenger extension that adds a number of useful features. Bundles the hard to remove C2Media LOP adware. The software does offer you a choice during setup - make sure to install MessengerPlus WITHOUT that "sponsor program"!
N	MessengerPlus3	MsgPlus.exe	MessengerPlus - third party MSN Messenger extension that adds a number of useful features. Bundles the hard to remove C2Media LOP adware. The software does offer you a choice during setup - make sure to install MessengerPlus WITHOUT that "sponsor program"!
X	messnger	[worm filename]	Added by the DELODER WORM!
X	messnger	Dvldr32.exe	Added by the DELODER.A WORM!
X	MeTaLRoCk (irc.musirc.com) has sex with printers	metalrock-is-gay.exe	Added by the RANDEX.Q WORM!
?	mfgboot	??	??
X	mfin32	mfin32.exe	MyFreeInternetUpdate - adware downloader
?	MGA Hook	Mgahook.exe	MATROX Graphics card related. What does it do and is it required?
N	MGA Quickdesk	MGAQDESK.EXE	For Matrox video cards. Quick access to tweak your card to your liking
?	Mgabg	Mgabg.exe	Matrox BIOS Guard. What does it do and is it required?
Y	mgavctrl	mgavrtcl.exe	McAfee's Virus Scan Online
Y	mgavctrl	mgavrte.exe	McAfee's Virus Scan Online
Y	mgavrtclexe	mgavrtcl.exe	McAfee's Virus Scan Online
Y	mgavrtclexe	mgavrte.exe	McAfee's Virus Scan Online
N	MGA_CD_Install	mgasetup.exe	Matrox Millennium video driver. Not required once drivers installed
X	MHDOGStart	mhdogst.EXE	Added by an unidentified VIRUS, WORM or TROJAN! A possibility is a trojan known as PENIS
N	MHINIT	MHINIT.EXE	Part of the Cybermedia Clean Sweep package
X	Mickey Mouse Cereal	[random filename].exe	Added by the RANKY.Q TROJAN!
X	Micr Update	soundblaster.exe	Added by the SDBOT.NP WORM!
U	Microangelo Desktop	Muamgr.exe	Quick access to MicroAngelo 5.0. It can make the background of the icon text transparent and also change the color of the shortcut's text to a color you want. Very useful, if you have a wallpaper. Available via Start -> Programs