There are Many
Software tools and measures to take:
No. 1 Must be Backup to external media (any user data)
Download and run
ATF-Cleaner (to remove all Temp files)
Run Internet Explorer
Reset (to set defaults)
Update
AntiVirus, and run a full scan
Run a
Malware removal program fully
Update all programs (ie Adobe; Shockwave; Java; Office.....what-ever is installed)
Update all
drivers from Manufacture Support page
Complete all
Windows Updates
Remove any unwanted Windows
Startups
Stop any not required Services (Start->Run->Services.msc)
Remove any Wallpaper; ScreenSavers; addon Themes etc
Remove any Not Required Programs (from Control Panel Programs group)
Run a CheckDisk in
Xp or
Vista
Run a full defrag
There are further
Hardware measures too:
Remove all internal Dust (using High compressed air can)
Re-connect all connections
Clean out all fans (including addon Video Cards)
Remove any unwanted other PCI cards (like old 56K Modems)
General cleanup outside computer (Screen and Case and Keyboard and Cables)
That's about the basics, but there are more
Advanced options:
Reset Network
Registry Maintenance
Running more Spyware removal Tools
Firewall and Hosts file configuration
Administrator passwords, and logon scripts
Bios update (including Modem firmware)
Actually this list can get involved, best to ask for support in this area
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