When a result is recorded against a unit using the Record Result Wizard, you are unable to remove it via the same process. The logic behind this is that Results are AVETMISS relevant data, so the act of recording this information works towards creating permanent information.
If a result is recorded in error however, you will be required to Remove or Reset that unit result to ensure that correct data is recorded.
Resetting a Unit/Module Result
To reset a Unit/Module result, you will need to look up the Clients' Enrolment in the Client Manager - Then expand the enrolment to see the Units linked to the Enrolment.
Right Click on the unit you wish to reset the result for, and select Reset unit/module result:
Upon selecting this option, the following message will appear: 
This is to alert you that the result will be removed, and the unit will then appear with no result.
Press Yes to confirm you wish to remove the result.
The enrolment will refresh, with the affected unit now displaying no result.
You can now feel free to record a new unit result as appropriate.
Viewing the Unit History for an Enrolment
There is a system report within VETtrak that can be accessed by Right Clicking an enrolment and then selecting the Show Reports option. The specific report is titled Show enrolment report with comments and history:
This will display the output for that Enrolment report, including a list of units with the history of actions recorded against that unit underneath each one:
