Delete Registry key using Install Script.
Here is the function you can use to delete a registry key in InstallShield project.
RegDBSetDefaultRoot( HKEY_LOCAL_MACHINE );
WriteLog("Trying to delete registry value for "+szKey);
szClass = "FPClass";
if (RegDBKeyExist(szKey) < 0) then
WriteLog(szKey +" can not be located in the registry. Deletion failed.");
MessageBox("Unable to delete the registry "+szKey,INFORMATION);
if (RegDBDeleteKey (szKey) < 0) then
WriteLog("Failed to delete the Registry.");
WriteLog("Registry successfully deleted.");
WriteErrorLog("Exception during deleting the registry key. The key is: "+szKey);