I got a Fujitsu-Siemens notebook with Windows Vista Home Premium and Norton
Internet Security (90 days for virusses updates).

The first problem I saw was that, after some time of having my notebook
turned on, I couldn't open new windows (applications, context menus, etc.)
unless I closed a/some window/s. And so on, until I didn't have any windows
to close and I had to reboot my computer.

One day the same happened again when I decided to scan some file for
virusses. Norton Insecurity Security window failed to appear. I reboot my
computer and still it didn't work: Norton couldn't scan my files. So I
decided to unistall Norton and reinstall it again. But I couldn't unistall
due to some error Norton told me. I did everything Norton suggested me to fix
that but nothing worked. And since I tried to unistall Norton it started to
appear bluescreen errors (my screen turned black and there were some colored
squares at the top of the screen).

As I couldn't use nor unistall Norton, I had to reinstall Windows, drivers,
applications... I decided to give a chance to Norton and I installed it again
(silly me!). I continued to have the same problem of windows that didn't
appear unless I closed other windows. I started to suspect that Norton was
the problem. So I decided to change Norton with Grisoft AVG Free edition
antivirus.

So I uninstalled Norton successfully. But a few seconds later, when I was
installing AVG, a bluescreen appeared! I reboot and tried to install AVG
again. Everything went ok. And....

Since then, I didn't have problems with my windows and the bluescreen went
away!!! Hope this helps to anyone.

P.S.: when I bought my notebook, the shop assistant wanted me to pay for
Norton Internet Security full registration... Imagine the situation of having
paid for it and wanting to uninstall it. No comments.