Again I have quoted this reply from a very similar problem that was listed on the Norton forum -
First run > http://go.microsoft.com/?linkid=9748992
<< M/soft Fix It installer helper -
This file is part of DING
is developed by Symantec Corporation.Last given solution =
While still connected to the Internet download the correct removal tools for each program onto that computer.
For the Norton computer it is the Norton Removal Tool found here: http://www.symantec.com/nrt/
Disconnect from the Internet and do a control panel uninstall and reboot. Run the removal tool and reboot
Install the security product of choice and reconnect to the Internet to complete the activation and do the necessary updating.
If you get the message that you have exceeded your installations contact the customer support folks here:http://us.norton.com/support/contact/contact.jsp?p?vid=cs
They can only help you with the Norton products but they do that very well.