Same thing for me now at my work PC :
Error (E30020)
But when I use my colleague's PC (just beside me) it works fine .. .. ..
I use FF and tried IE same crap (not going to try Opera either) since it works fine with FF here beside me .. .. so it's a settings somewhere .. but what ?
I haven't added anything these last few days .. .. except maybe a FF update ?
I did a Clear Private Data ..
I use a Portable FF 3.0.19
I tried with the works FF on this same PC : FF 2.0.0.12 (not able to upgrade it, Work polities) and it worked ok ...
I'll keep trying stuff and let you know here