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Norton Antivirus real protection failed to load

Posted on 2005-03-22
Medium Priority
Last Modified: 2013-12-04

I am suddenly having a problem with Norton Antivirus 7.51.856.
The error I am getting is: "Norton Antivirus real protection failed to load". The shield has a a red diagonal line across.

I tried un-installing and re-installing the client, but I am Still getting the same error.
Any help will be appreciated.

Question by:novice12
LVL 12

Expert Comment

ID: 13606018
What have you recently loaded on to your machine?  That old version of NAV conflicted when run with BlackICE and some other personal firewall software because BI would lock the Service Control Manager database and would cause loading of AutoProtect services to fail.

Also, this issue has been seen many times and has one common source of problem, if you contact Symantec about your problem there have been reports that Symantec offers a NoNav" unsupported fix .bat which fixes this problem.

Here's more info on it:
LVL 29

Expert Comment

ID: 13606947


This will remove NAVCE and Symantec AV version 4, 5, 7, 8, 9, SCF, SSC, and AMS from the filesystem and registry, and restart the computer.

Use at your own risk (I have...).

LVL 11

Accepted Solution

ghana earned 2000 total points
ID: 13611407
As already mentioned by Phil_Agcaoili BlackICE could conflict with NAVCE. Symantec describes the same error message after uninstalling PC-Anywhere:
To solve that there is a patch available.

Sometimes a corrupted virus definition file is responsible for that problem. To fix this you have to 'roll back' to the last known good definition. Please go to the folder C:\Program Files\Common Files\Symantec Shared\VirusDefs and check the content of the following files:

Definfo.dat will look similar like that:


Copy the string behin "LastDefs=" to "CurDefs=". So both def versions will be the same. Save the file. Usage.dat will look similar like that:


Change the content between the brackets to the same string you have copied to CurDefs in Definfo.dat and save this file too. In the example above the conent of the files should be:



Now look for the subfolder that is named exactly like the ORIGINAL value behind CurDefs. In the example above the folder must be named:

Delete this folder. As a result you will only have the string behind LastDefs in both of the files and also one subfolder with this name. Now try to start the NAVCE service again (or reboot the computer).

Hope this helps.

Author Comment

ID: 13612710

I did not install/unistall any new software recently.

I decided to try the simplest approach first, sugested by ghana, and it worked. So it looks like I did have a "corrupted virus definition file".

I have to mention the fact the I could only delete the virus def folder in "safe mode".
I did a virus definition update afterward and it's working fine now.

Thank you all. Yo have been very helpfull.


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