I've been able to use system restore (SR) for many years, with various incarnations of NAV and NIS. NIS 2011 results in a browser protection corruption and the sole solution is to remove everything and reinstall. It's such a pain the you-know. I disable tamper protection so SR works, but if it ruins NIS, I am seriously thinking of changing to a protection suite that doesn't cause additional problems. If older versions permitted SR, why not the latest one? I do not accept that the best protection can't incude a way of protecting own files during SR. I only reverted to five days ago and while live update updated beautifully, browser protection did not.
Welcome to the Norton Community. What version of NIS do you have? You can find this from Support > About. Also what version of Windows and SP (service pack) do you have and is it 32 or 64 bit?
Tamper protection is the very thing which does prevent other programs (including the OS) from modifying critical Norton files. But since system restore backs up some of the Norton files, Windows will not allow the system restore to complete unless it is able to restore ALL files which comprise the restore point. There is nothing Norton can do to prevent that.
Many times system restore can be used without adversely affecting your Norton product but yes there certainly are times when it can cause NIS to become corrupted such that it has to be reinstalled. Largely this can happen when your Norton product has gone through a live update which takes it to a new version number than what it had when the system restore point was created. It can also occur when there are other program updates in between those two points in time.
System restore is most useful when you have installed some new driver or software which has made your computer unstable or creates other serious problems and in that case you can probably use system restore to recover from it without adversely affecting your Norton product.
But the longer the time between the restore point creation and the actual restoral the higher the odds are that it might affect Norton.
You might want to also consider investing in an imaging backup program like Norton Ghost. This is much more complete protection as it backs up your entire system to where you can truly restore to any point in time in which you have a backup image.