I have Norton Internet Security 2010 installed on my Windows 7 64-bit PC (latest version of NIS 17.7.0.12).
This evening I downloaded a file from the net and went to perform a quick file scan on it (right click and select Norton Internet Security / Scan Now), however, nothing happened, no scan was performed.
I rebooted my PC and tried again, but as before no scan was performed.
I opened up the NIS control panel and selected Run Custom Scan (from the drop down next to Scan Now) and under custom scan selected File Scan) on the selected file but again no scan was performed.
I tried to scan other individual files on my PC and these too failed to perform a scan.
I also noticed that when the file download completed I didn't see the usual NIS Scan message pop up in the bottom right corner of my screen.
I don't tend to download a lot of files so couldn't precisely say when I last recalled seeing this scan work, but it certainly has worked fine (as indeed has File Scan) within the past month.
Please can someone shed any light on why my File Scan (and automatic download scan) have become disabled?
I have checked the settings and I can't see anything has changed and I am the only person who uses this PC and I have not made any setting changes at all.
**update**
I also can't perform Run Quick Scan or Run Full System Scan. This is becoming very strange (and more than a little worrying). However, idle scans seem to be taling place okay from what i can see on the logs.
Is this a recent installation of NIS? Was there any other antivirus program on board before installing Norton? When the update to the new version occurred, did it call for a reboot?
You may have a problem update, which will probably entail removal of NIS and reinstalling. Unfortunately, the newest version isn't available for direct download as yet so far as I am aware. You will need to reinstall a slightly earlier version, and then use liveupdate until the new version downloads and installs. Then reboot whether it calls for it or not.
You should be able to remove it through add/remove since you are reinstalling.
http://www.symantec.com/norton/support/kb/web_view.jsp?wv_type=public_web&selected_nav=&pvid=&docurl=20090121104844EN
This is a brand you install from shop bought version of NIS 2010, and I installed it just a little over 4 months ago onto a brand new PC which didn't come with any pre-installed AVS.
I have been able to File Scan in the past and in fact I have noticed that today the automatic scanning of downloaded files is working (after i went on the Norton site and saved the application to check I had the latest version installed on my PC).
However, I still can't perform a File Scan and I have noticed that for each File Scan I try and run there is a corresponding number of instances of navw32.exe *32 sat in my Processes but not using up any CPU time.
The other thing I noticed last night after checking my Norton Security History was that for each time I tried to File Scan there is an instance of blocked activity:
Hope this information is useful and thanks for your help so far 
Hello
It will take a little time for the Mods to approve your picture before everyone can see it. Thanks
Hi Maroba1964:
Your image doesn't indicate a problem. It is an internal Windows function that is trying to access to deeply into Norton files. Norton is blocking the access, without stopping the function entirely.
You can click under Help & Support>One Click Support and have the scan check for problems. It may self-correct that way. Otherwise, I suspect that it will be an uninstall and reinstall. Since Norton came pre-installed on your machine, we don't know how many engine changes it was behind before the new version was installed.
Thanks delphinium, I uninstalled and reinstalled and my File Scan, Quick Scan and Full Scan are all upand running again 