All internet browsers get certificate error even after correcting date

Hi guys i really need help
I can't get rid of security certificate error. It happened because i accidentally set wrong date in BIOS (i wasn't using it about 3 month and CMOS batter was dead therefore it asked me to enter the date). After using it couple hours i saw that error and googled it. I found that the date is wrong and fixed it but nothing changed. I still get that error almost on any web page i enter (on all browsers:Firefox, Opera, IE9).
Please help me to solve this problem, cause its annoying to click Continue to this website (not recommended) on IE or add exception on Firefox.

And also can it be a firewall or antivirus issue? I've Nod32 ESS x64 installed.

Thanx for answering :)
I've just installed all available updates and restarted couple times but still no change

Everything is correct in the date. I've checked that 1000 times.
And also i've tried removing cmos battery and resetting in BIOS but no luck (((

I can't run run SFC or repair install cause i've modifed some system files (for theming) and i dont wanna lose them.
There must be a better way some kinda resetting something, i'm sure it happens because i set wrong date in BIOS.

And by the way i know it doesn't concern this topic but when i log in to my pc after sleep or just start i get limited access on my wifi and i get internet access after 3-5 mins. I don't know what happened but i always used to get internet access instantly before

i think nobody has a clue how to fix this (((
I even get certificate error on Vbox machines on any guest OS, and also i can't back up my iPhone on iTunes (after googeling around i've found that back up error as well as iPhone software update error in itunes is because of incorrect date). But the date is correct (((. I even did a SFC scan but no luck. I can't restore couse i don't have restore point before that happened. And also i've no recovery cd. I've totally disabled both windows and ESET firewalls and still...........

i guess i need a miracle to fix this s#!t
hope somebody finds this miracle

ok now i'm doin a repair install with Windows Ultimate x64 DVD. Everything was fine untill restart couse now i stuck on 18% of "expanding Windows files" for almost 4 hours. It says "Gathering additional information before expanding files "
Should i run it again or it's normal that it takes that much time?