Quite often I get a message saying the NT System Kernel and the NTOSKRNL.exe want to access my computer. I use Sygate Personal Firewall and the NT System Kernel is checked to "Allow." Yet I still get these messages. If I click don't show me this again, it continues to show it the next time. Any idea how I can turn this off, it's driving me crazy? Thanks.

Use a different Firewall. NTOSKRNL.exe has to be always allowed. shame on Sygate for flawed software design.

I also have Sygate with the exact same problem. I believe you can right click on the Sygate tray icon and check "Hide System Tray Icon", but while this may hide the message from popping up, it won't stop NTOSKRNL.exe from being blocked. I may switch firewalls, but I tried Zone Alarm and it didn't work well with my pc. So, is there another suggested firewall? Thanks.

Sygate SSE and SPF Security Agents will block all ports and protocols exposed to the Internet by ntoskrnl.exe. It can be used to expliot a serious security hole with windows. DOS attacks aimed at port 445 including SYN floods are denied with no adverse affect to Windows XP. Thanks to www.safehack.com for the disclosure of this serious exploit. The only effect you might see is that your file and print sharing might not work. You can enable this again by allowing traffic to the file.