Norton internet security disabled AGAIN!!!

Please someone help - getting seriously hacked off wiht Norton. Have Internet Security 2009 which I downloaded the upgrade to 2010 to last night. Fired up my PC this morning and no internet security. No icon on bottom right corner of screen and when opened on start up menu I get redirected to one click support and there I keep getting error message ‘hsie 2010 application encountered a problem and needs to close’. So am running my pc without anti-virus - how do I get it turned back on ? Please help!!