your pc is on slef assings ip address mode which is normally used for VPN connection, if it happen you need to check for updats in you computer actually
It is possible that you may have performed a software or "os x" upgrade and there were some errors in the bits being transfered to your machine.
Please open up your console log and go to /Library/Logs/'Software Update.log'
check that if you can find any thing by date over there when u were last on internet
Look for something in the log that specifies your last "Mac OS X Update", it will also be dated. In addition, look for the log that specifies your last "Security Update..." which is also dated. Please post back the Installed date with the version of the updates for both.
It will be something like:
2006-10-03 19:17:31 -0700: Installed "Mac OS X Update (PowerPC)" (10.4.8)
2007-02-17 14:47:45 -0700: Installed "Security Update 2007-002 (PowerPC)" (1.0)
Let's see if this is in the time frame that you started to experience your problem. Please list any other updates as well that may be in the time frame when you started to experience this problem.
Even if it isn't, you may want to reinstall both the "Security Update" and "Mac OS X Update" with the combo updater from Apple.
You can find it at the following url:
Apple - Downloads - Mac OS X - Mac OS X Updates
Apple - Downloads - Mac OS X - Security Updates
To find other applications that you may have installed during that time, you will need to open 'System Profiler' by doing the following:
Go to the Apple menu in the top left corner of the screen. Click on About this Mac. Click on 'More info...' Go down to Software -> Applications. A list of Applications will appear and the last date they were modified. This will also be a good time to go into Network and take a look at the information under Airport Card, so please post back this information if it looks strange.