Registry files (.reg files) allow DemandTools administrators to control which Salesforce instance a DemandTools job starts in. When using JobBuilder or another scheduling tool, it is possible to run a couple jobs in one Salesforce instance and then jump to another instance to run more jobs.
The registry file determines which login information should be stored in the Windows registry (assuming save password is set to on). It has always been a best practice for scheduled jobs to have each line specified by a .reg file to avoid accidentally running a scenario in the wrong instance.
But this can be a slight pain to an administrator who doesn't want to leave login information in the registry or just wants to reset/erase what is stored in the registry.
The attached .zip file contains a .reg file that blanks out DemandTools login information for the default login icon. It will not remove credentials from org specific registry files.