comodo doesn't start on switching on

Hi, I have comodo ver which I have been using for quite a few months with no problems. Over the last 7/10 days it does not startup when I switch on the computer, I always get a balloon saying it is switched off and the only way I can get it switched on is to open the program from start/programmes menu. Using broadband (dsl, akways on) that probably means that my computer’s not protected for those few minutes as I can’t do anything until my desktop is loaded.

I have read where this could maybe be attributed to a virus/trojan. I have run avg av, avg spyware, super antispyware, spybot s&d and spyware blaster but all that came up were some tracking cookies. Can someone help, please. Thanks for reading and in advance for any help offered.

I am using xp pro sp2.