question about ntoskrnl.exe

[mysts]

We have a computer running windows xp pro.
Every couple of minutes a little window pops up in the lower right of the screen with the following message: "ntoskrnl.exe has been blocked from accessing the internet"
We would post an image of the little box but it does'nt stay visible long enough to capture.
Is this something to be concerned about?

[jmohn]

Sounds like it's time to do a virus scan. Ntoskrnl.exe is a valid XP file but it can be corrupted by viruses. Undwer normal circumstances you shouldn't be seeing any window referring to this file.

Jerry M

[redwudz]

ntoskrnl translates as NT OS (Operating System) Kernel : http://en.wikipedia.org/wiki/Ntoskrnl

You might look here for a possible fix: http://www.computerhope.com/issues/ch000646.htm

If it wasn't working, the computer wouldn't boot, so another explanation is a virus or malware causing the problem or the popup. If it wasn't working you would usually get a MS warning of 'ntoskrnl is missing or corrupt' or similar at boot and the OS wouldn't start. What program is giving you that warning? Sounds like a anti-malware program warning, not the OS. I would run a scan with something like MalwareBytes: http://www.malwarebytes.org/mbam.php

[isogonic]

a little window pops up in the lower right of the screen with the following message

Do you have a software firewall installed? Or a security suite like Norton or Mcafee that includes a firewall?

[mysts]

Sorry to take so long to wind this up but my neighbor(client) had to leave for a while. When he got back we tackled this problem again.
Here is what we did. We went into safe mode and ran three registry cleaners one after another, then a trojan remover, then an antivirus, then an antispyware. We then rebooted and the problem was no more.
So we do not know what caused the problem nor what fixed it.