First of all, let me say, I'm sorry. You're using Windows.

That said, this is a simple and easy guide to cleaning and maintaining XP or 2000. Most of it applies to ME/9x but installing updates is constrained to manual Windows updates runs over and over.

First, we patch your copy of Windows up to date.

Make sure you don't already have it, then grab the latest Service Pack for your Windows version:
Get it, install it, reboot as many times as it prompts you to.

Look, you're prettier and less vulnerable to the world. Note that pre-XP installs have no built-in firewall, so you kinda need a router or other firewall between you and the world.

Next, we install the various updates since the Service Pack came out.

Also, as long as the latest version of AutoPatcher is December 2005, grab the version of this patch for your OS, it fixes a nasty problem that I don't have time to go into here: Update.

Good, you're patched. Now it's time to start cleaning, now that most of the backdoors are closed.

Get an antivirus program.

I don't trust you to maintain anything else. Get one. There are several free ones (AVG and Avast! come to mind), and some nonfree ones (Symantec and NOD32 are the ones I'd recommend).
Install. Be merry. Make sure it autoupdates regularly. Scan your whole system after updating the virus definitions to the latest versions.

Good, you have antivirus.

Clean out your spyware, then come back here.

Spyware clean? Good.

Go get CCleaner.

Install, run, press the Run CCleaner button (not Analyze). That will clean out all the miscellaneous cruft Windows left behind.

Yeah, I can't think of much else. Just go to Windows Update or Windizupdate once a month or so after that, and update Ad-Aware/Spybot/MS Antispyware/your antivirus every two weeks [or daily when you hear about some big nasty thing] and run scans every week.

Feel free to contact me about any questions, Rincebrain+spyware@gmail.com.

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