Reinstalling

First things first: make sure you are reinstalling/restoring for the right reason. Generally this will fix any and all software problems you may have: viruses, spyware, bad drivers, failed update or removal of a program, registry errors, etc. It is also a very good idea to reinstall/restore Windows if you bought a second-hand computer. However this will not help if your computer has any hardware problems. Use the “Hardware” section on this site to try to identify and fix any hardware problems first.
All laptops come with some means of restoring or reinstalling the operating system and software. Some, like most Dells come with a Windows CD and drivers/software CDs. Others like Toshiba and Sony come with HD image based restore CD/DVD sets. All Macs come with reinstallation DVD sets, and most of the rest come with a restore partition on the hard disk or a combination of CD and partition.
On all computers that have a hidden restore partition on the hard disk, there is a utility that will let you burn your own restore CDs or DVDs. Also you can purchase that set from the manufacturer, usually for a nominal price covering just the shipping and handling. Of course, if you are restoring to a new hard disk, you have to have these CDs or DVDs.
There are several steps in reinstalling/restoring the software on your computer: backup your files, reinstall the OS, install any new or updated drivers, install and update your antivirus, antispyware, firewall, etc. update Windows, install and update your software, copy your files back.

Backup

If your hard disk is damaged and you are replacing it, you can try to copy any files later, after everything is installed on the new HD. If you are reinstalling because of a virus infection and Windows wouldn’t start to allow you to copy your files, you have two options: take the HD out and use an external USB box to transfer your files to another computer, or make a bootable CD, start your computer from it and use an external USB hard disk or a flash drive (with enough capacity) to store your files temporarily. It is also possible to start your computer from a bootable CD and copy your files to another computer over a network, but that would take much longer. And of course if you are one of the lucky people that has recent backup, you can skip this step completely.

Reinstall or restore Windows

If you are restoring from a CD, make sure your computer starts from it (usually press “F12” or “F8” as soon as you see something on the screen, or change the boot order in the BIOS). If restoring from a partition, see your documentation on how to start the process (“F11” on Gateway, “Ctrl” + “F11” on Dell, etc.).

If you are installing from a Windows installation CD, you have more options. Do not choose “Repair my current installation” option just after you press “F8” to accept the license. This only works if your Windows files have become corrupted after installing a new driver or new update, or after changing the motherboard on a desktop PC. When you are reinstalling because of a virus infection, best is to delete the current partition and let the installer partition and format your hard disk again.

At this point you have the option to split your hard disk into two (or more) partitions. This is indeed a very good idea, as you can install Windows on “C:” and keep all of your files on “D:”, so when you have to reinstall Windows again, you can format “C:” and all of your files will remain untouched on “D:”. Some laptops come setup that way by default – all Sony, some IBM, etc. You will usually need 8 to 10GB for Windows and all of your programs, and the rest for storage.

To do that, after deleting the existing partition (press “D”, then “Enter”, then “L”), create a new one (by pressing “C”) and change its size to 8000 for 8GB or 10000 for 10GB “C:” partition. You can leave the rest of the hard disk unpartitioned for now. Then install Windows and as soon as it finishes, go to Control Panel -> Administrative Tools -> Computer Management, then click on “Disk Management”, then right-click on the unpartitioned space of your hard disk and choose “Create Partition”. Follow the prompts to create and format a NTFS partition. After it finishes formatting, this will appear as “E:” drive in “My Computer”.

If you want to change the drive letter to “D:”, right-click on your CD/DVD drive (still in “Disk Management”) and choose “Change Drive Letter and Paths…”, then click “Change”, then select anything after “F:”, then click “OK” and dismiss the warning. After that repeat these steps for the second partition you just created (right-click on it… etc.) but choose “D:” for the drive letter. After that repeat again for the CD/DVD drive choosing “E:” as the drive letter and close the Disk Management/Computer Management utility. It is best to perform this step immediately after creating a new partition or formatting an existing partition, as all the references to any files that are currently on the partition will change.

Now go to “Control Panel -> User Accounts” and create a new “Limited User” account (you can use any name and password for it). Then log off (Start -> Log Off -> Log Off) and log on the new account. Now go to “Control Panel -> Display” and choose the second tab “Desktop”, then click “Customize Desktop”. Now check the “My Documents”, “My Computer” and “My Network Places” checkboxes and uncheck “Run Desktop Cleanup Wizard Every 60 Days”, then click “OK” and “OK” again to save the changes.

Then go to “My Computer” and open “D:” (or “E:” if you didn’t change the drive letter), right-click on the empty space there and choose “New -> Folder” and rename the folder to “My Documents”.

After that right-click on “My Documents” on your desktop and choose “Properties”, then click on “Move” and select “My Computer -> D: -> My Documents” (the folder you created earlier) and finally click on “Apply”. Windows will ask if you want to copy the content to the new folder, click “OK” and “OK” again to close the control panel. Now all of your documents will be stored by default in the folder you created on the “D:” drive.

Drivers, Antivirus, Windows Updates
If you have a separate drivers CD (like most Dells), install all drivers now. If you restored from a System Restore CD set or partition, all drivers should be already installed. If you are still missing some drivers (check in “Control Panel (click on “Switch to classic view” on the left) -> System -> Hardware tab -> Device Manager”), you will need to download them on another computer and copy them to a CD or a flash drive and then install them on your computer. All drivers for nearly all brands and models of laptops can be fount on the manufacturer’s support web site.
There is a very handy utility in case you don’t know what drivers you need: UnknownDevices.exe. You will also need to download the pcidevs.txt file http://members.datafast.net.au/~dft0802/downloads.htm and put it in the same folder as UnknownDevices.exe and run the utility. UnknownDevices will scan all the hardware on your computer (the PNPIDs) and for each “Unknown Device” it will give you the chip model, the chip’s manufacturer and the device manufacturer, which on a laptop is always your laptop manufacturer.
After all drivers are installed, connect to the Internet and install your antivirus, antispyware, personal firewall, etc. and update them all. Then go to “Control Panel -> System -> System Restore” and move the slider all the way to the left, giving it 200MB of disk space. The Windows System Restore is useful in only two occasions: if a driver or Windows update doesn’t install properly and the computer wouldn’t start in normal mode but still starts in safe mode, or if your registry files become corrupted and (after ruling out hard disk and memory problems) you want to restore your registry by hand.
Now still in the “System” control panel go to “Automatic Updates” tab and select “Notify me but don’t automatically download…”. Then click “OK” to save the changes. After that Automatic Update will pop-up pretty soon telling you that two updates are available. Download and install them, then restart when done. Now Automatic Update will pop-up again and will tell you that there are over 60 updates available. Now is the time to go to “Advanced…” and uncheck any updates you may not want at this time, like the new (at time of writting) IE7 or the somehow controversial “Windows Genuine Advantage”. Download and install the rest. Or if you prefer, run Windows Update.
Install your software and copy your files back
At this point I would strongly suggest to download and install either Firefox or Opera and use any of them as your main web browser. After that install all of your software and check for any updates for it. And finally copy all your files back to “My Documents” and the desktop.
If you backed-up any emails, you will have to import them back after creating your email account(s).
For Outlook Express select “File -> Import -> Messages -> Microsoft Outlook Express 6 -> Select “Import mail from an OE6 store directory” and click “OK”, then navigate to the folder that contains your .dbx files and click “OK” again to import them.
For Outlook: select File -> Import and Export -> Import from another program or file -> Next -> Select “Personal Folder File (.pst)” -> Next -> Browse and select the copy of your outlook.pst -> Next -> Finish.
For Thunderbird: make sure Thunderbird is not running, then copy the folder to exactly the same location “C -> Documents and Settings -> [your user name] -> Application Data -> Thunderbird”.
You can import your bookmarks in Firefox or Opera from whitin the program.
The folder “Application Data” is usually “invisible”. To be able to see it you will have to enable “Show hidden files and folders” temporarily in Control Panel -> Folder Options -> View.