Ndis.sys is a file that is a part of the Microsoft Windows operating system such as Vista, XP, and Windows 7. Ndis.sys is a system driver within the core components of the operating system. In most instances the Ndis.sys file is found in the system32 folder, which is located in the Windows folder on the driver that the operating system is installed to. There are times when the Ndis.sys file will have issues with it and require some fixing to ensure that Windows continues to work correctly, and those ways of fixing the Ndis.sys are listed below.
As this file is important to the correct operation of Windows it is important to ensure that the Ndis.sys file is always present on your system. There might be times when a Blue Screen with a specific error code presents itself on your monitor. If the error message refers to Ndis.sys files then it is very important to copy down the error message as well as any location information as this will make the problem easier to locate and resolve.
In some instances a Trojan has been known to reside in the same location as the legitimate Ndis.sys file and display a very similar name to Ndis.sys. This is to try to avoid detection and identification by the user so it can continue to run its malicious activities on the system.
If you think that there might be a malware infection on the system that might be causing Ndis.sys error messages then the best thing to do is to download a security program and run a full scan of the system, often called a deep scan, so that it will check the Windows system files and see if Ndis.sys is in fact a Trojan or a legitimate file.
Another issue that is known to occur relating to the Ndis.sys system file is that, when using Windows XP, there are times when the older service packs might have issues within the file itself and cause issues. This is because the Ndis.sys is the default driver with Windows and as users make changes to the system the Ndis.sys file might become unstable. If Ndis.sys becomes unstable then there is the possibility that error messages will be displayed referencing the Ndis.sys file itself.
If you think that this could be the cause of the errors starting on your system the easiest thing to do is to download the latest Service Packs for the Windows operating system that you are currently using.
The last reason that Ndis.sys errors typically occur is due to a corruption in the files of the Windows operating system itself. If you think that this could be the cause of the issues then there are two options, either re-install the operating system and possibly lose your personalized information and data that is on the hard drives; or run a registry cleaner and try to fix any of the problems in the registry of the system.
There are times that a deep registry scan can resolve Ndis.sys error messages as the Windows registry is the brain of all the activities that happen and registry cleaners can often fix .sys error messages.