Use the uninstaller to remove Instant JChem from your machine.
Double click on
uninstall.exe in the Instant JChem’s home folder
Select Instant JChem from the Add / Remove programs list on Control Panel.
Select “Instant JChem’s uninstaller” from the “ChemAxon/Instant JChem” menu from the Programs menu (which you can access by pressing the “Start” button on the toolbar).
Drag the icon of Instant JChem into
uninstall script in the Instant JChem’s home directory.