Hi Pieter,

Yes, I have this feature using a Pendrive or Memory Card (external media).
Here I am providing just an idea of ​​what I did and considerations:

1) Windows application.
2) The name of this table: Token (Embedded Dataflex). Too many system tables in SQL.
For obvious reasons, this has to be in Dataflex (Embedded), so I can write to any drive mapping, which is removable.
Maybe some SQL expert will say that this is possible to do in SQL.
3) The token is directly associated with one or more devices, which have been previously configured for this purpose.
This doesn't seem to fit what you want.
Attempting to use the Token on other equipment that has not been generated, you will not have access to this Token.
4) This token can consider access levels, such as:
- Mandatory without entering a password, so the login is only granted if the Token is present.
- Mandatory + password entry, this is the maximum level since, in addition to the token, the password must be entered.
- Optional token, can be present or password, must be typed.
- Token with restricted privileges a kind of access level.
5) The process is controlled in the user registration, so in this interface I revoke or create a token, which has been lost.

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Best Regards,

Edgard L. Paneque