I just spent over a day of my time (4 tech chats who couldn't help me) and $99 for a virus expert (symantec) who said he found the following virus 0D3E0DE856.sys on my system. He wouldn't reply to my query as to whether he was sending the virus to be investigated. He did say that it was a new virus and didn't have a name. I asked him when the virus was installed and he said he couldn't tell me since it he had destroyed it. I question whether he really found a virus since I have always used NAV and never gotten a virus let alone a "new and unknown" one.
The problem started as error messages "Symantec Service Framework" closes and the icon on the toolbar disappears. At which point you can't open any NAV program without rebooting.
The virus expert said it was affecting my registry.
Other errors came up over the course of 10 days - explorer.exe and ccsvchst.exe
I installed NAV09 twenty days ago and the problem came up 10 days later. Reloading it didn't solve the problem.
I spent 3 hours online tonight with the paid technician. No errors have occured since he completed the work. The jury is out on this one.