Windows Vista License Issue After Endpoint Protection Installation – Unauthorized Change to Windows

If you are implementing (or going to do in future) Symantec Endpoint Protection (SEP) 12.x client on your personal or company computers which having Windows Vista, better read this simple post. I have experienced Windows Vista license issue during SEP 12.1 installation in the company where I’m working.

Users can’t login to their computers after SEP 12 installation. The welcome screen will display ‘Unauthorized changes to Windows has been made’, and it will ask to you activate Windows again. The sad part is, you can’t login even if you wish to activate, a force logoff will be done after pressing OK for above warning message.


How to Fix?

It is very simple, Symantec recommends to install the latest Windows Vista Service Pack. You will be getting this Windows Vista license activation issue after SEP 12.1 installation on all Vista computers running with SP1 or without any service packs. Also, this can happen only sometimes. So, it is not a certain issue after the SEP 12 installation and restart SP1 or earlier Windows Vista computers. But defiantly this will cause issue if you do not update these computers to Service Pack 2. It is better to update now.


Two things can be done.

1) Before install the SEP 12.1 or later versions, install Windows Vista SP2 on the computer.

Windows Vista SP2 can be installed on SP1 only. You can’t run standalone SP2 update on a computer which is not having installed Service Pack 1 (SP1).

Here is the official download link of;

Windows Vista SP2

Windows Vista SP1

Unfortunately, installing both service packs took more than 1 hr and 30 min for me 🙁

After above two updates, SEP 12.1 can be installed without any future issues.

2) OK, by any chance if you already installed SEP12.1 without checking the Service Pack and now getting Vista activation error which prevents to use the particular computer, then what can be done?. Obviously you can’t login to computer to update the service packs in normal mode now.

Here is the simple way,

Restart the computer and press F8 to get advanced booting options.

Select Last Known Good configuration booting option. It will take some time to restore and load with your previous successful login profile. If it is a Vista SP1 computer, you can directly update it to SP2 and use without any issues by SEP12.1.

But, if it is not having SP1, I suggest to uninstall SEP12.1 before install SP1. Because after the SP1 installation you need to restart the computer again (even before begin the SP2 update), so possibly you may get the same error on next restart because still SP2 is not installed.

So, uninstall SEP 12.1 in last known good configuration, install SP1 –> Restart, Install SP2 –> Restart and now install the SEP 12.1

Definitely it will work without any issues. I have experienced this issue and solved it by this service pack update while implementing in our company. Also, it is recommended by Symantec here.





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