Securely Removing Personal Data from your Corporate Windows Computer

You have been using your company computer for your own private use, especially if it is a laptop. Now you want to securely remove the personal data off of the company equipment. First place, it's not wise to store your personal data on a company computer. People can and do look at it, especially if there are issues with your equipment. There may be laws that cover those files/emails as private property, but that's not going to stop everyone from snooping and possibly gossiping. There are ways of opening up files and looking at the contents without the system logging it.

WARNING: Do not remove data that pertains to the company. It can get you into big trouble. You could possibly lose your job. It could even go as far as civil and/or criminal court. Only remove data that is strictly personal.

Here is a list of the things you will want to clean off of the system:

• E-mail
• Applications
• Files
• Pictures
• Music
• Videos
• Browser
• Bookmarks
• History
• Cache
• Cookies
• Passwords
• System Restore Points

Limitations

• If your company backs up the data on your system, it's not going to do a lot of good to securely delete everything because they will have a backup of it.
• Most companies retain data for a period of time on the exchange servers. They will be able to recover the emails from the server if the retention period is still active.

Here is the process you will want to follow in this order to securely delete all of your personal data:

1. Export all of your personal emails to a pst file if it's Outlook, or a csv/txt/xml file for any other email type. You may also want to check inside your company email inbox for personal emails and export them out, or forward and delete them. 
2. Delete any personal email accounts that might be associated with Outlook.
3. If you were using Outlook, the emails will also be stored in an OST file that you might want to think about deleting. It will be recreated the next time you open Outlook, but this time it will not contain the emails from the personal accounts you deleted. The OST file is used to cache down the emails for quick access.
4. Export your personal browser bookmarks to a text file.
5. Export your browser cookies if you prefer. 
6. You can't transfer applications to a new system, so you will want to get your application licensing information, such as product keys, and then uninstall the applications.
7. Transfer the files/music/videos/cookies/pictures/exported emails/bookmarks either to a USB thumb drive or to the cloud.
8. Uninstall any cloud drive applications that link your system to your cloud storage.
9. Next, you will want to delete the personal files. While deleting files, include the %TEMP% directory. This contains temporary files that should not hurt anything on the computer if they are deleted, but there may also be personal files stored there. 
10. Use CCleaner to clean up your system of all cookies, temporary internet files, browser history, index.dat files, recycle bin, temporary files, and more.
11. Delete all System Restore Points. The restore points can be used to restore data that you had deleted off of the system.
12. Create a new system restore point. This will be created without the data of all the files you have deleted.
13. Use CCleaner to clean up the registry. It is recommended to use the registry backup feature before deleting any keys. 
14. Use CCleaner Drive Wiper (Free Space Only) to wipe all free space sectors. It is recommended to overwrite with 3 passes. This will stop anyone from being able to recover a system restore point or files. This process will take a long time, so it's recommended to do it at the end of the day. You can learn more on data deletion here.
15. Create a new system restore point.

That should cover everything for most users on securely removing your personal data from a company computer.