We're thinking of developing a limited application capable of permanently deleting email messages. The idea is that once the user deletes the message (from say Outlook Express or a similar SMTP/POP3 application), the message is actually overwritten on the disk, so as not to be recoverable via normal off-the-shelf file recovery or forensics software. We're not certain that we have all of crucial issues on the table; for example,
- How might we deal with XP disk caching?
- Is there a way for a separate application (such as a service) to "know" when an Outlook Express email has been deleted by the user, to then locate it, and write over it?
- Is there some virtual operating system possibility of collecting files to a thumb drive and "designating" that location as the only location the files could be written?
- Has anyone already done this commercially, i.e. could we just go buy it off the shelf today?
- What other issues are there to consider?