One-factor authentication (user IDs and password) is still the most widely used method, primarily because it is simple, easy and there are no pieces of hardware to configure. But there are many applications where this is just not secure enough. In two-factor authentication, not only do users need to know a PIN but they also need to possess the correct token. This higher level of security, combined with the token's memory and cryptographic processing capabilities, makes it particularly attractive as a solution for many situations such as digitally signing documents and mails and authenticating the user remotely for access to corporate networks through VPNs.
The problem of recovering accidentally deleted files was solved largely by the implementation of the recycle bin in Windows - allowing users simply to select 'Restore' from the right-click menu. However, there are a number of users that will, without thinking about what they are doing, automatically empty the recycle bin or even use a utility that does it for them at the end of each session. In addition to this, some viruses delete files, bypassing the safety-net of the recycle bin and of course, some malicious users will deliberately remove certain files. In response to this, O&O Software GmbH has written O&O UnErase which provides the user with a means of recovering such files.