Just check it to make your XP faster.To disable unneeded startup services for a safer, faster XP, use the "Services" Admin Tool (Control Panel > Administrative Tools > Services). If you are a single user of a non-networked machine, you can disable the following items, with no ill effect.

1. Alerter
2. Clipbook
3. Computer Browser
4. Fast User Switching
5. Human Interface Access Devices
6. Indexing Service (Slows the hard drive down)
7. Messenger
8. Net Logon (unnecessary unless networked on a Domain)
9. Netmeeting Remote Desktop Sharing (disabled for extra security)
10.Remote Desktop Help Session Manager (disabled for extra security)
11.Remote Procedure Call Locator
12.Remote Registry (disabled for extra security)
13.Routing & Remote Access (disabled for extra security)
14.Server
15.SSDP Discovery Service (this is for the utterly pointless "Universal P'n'P", & 16.leaves TCP Port 5000 wide open)
17.TCP/IP NetBIOS Helper
18.Telnet (disabled for extra security)
19.Universal Plug and Play Device Host
20.Upload Manager
21.Windows Time
22.Wireless Zero Configuration (for wireless networks)
23.Workstation.
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