Resolved FF won't show email

I use Yahoo and in FF the messages are blank, yet in IE they are fine.
Last night the computer said I was infected, though I thought it was some scam and I shut down the window. Everything else seems fine. When Avira AntiVir ran last night it showed everything as fine, and it's updates are current.

 

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Can you be more specific? Did Avira reported something wrong. Like what?
I have AVG, and early this afternoon it reported a threat, but did not offer to quarantine it. Actually, it did not even show what kind of threat, but only the website.
I am using Super Antispyware, and a scan indicated a trojan. I quarantined it. A rescan indicated a clean system. I don't know if it did the job (the trojan tends to come back), but I satisfied with the results, for now. I don't save any cookies, but previously to the change in the options, I had hundreds. I suggest that you get Super Antispyware, get a scan, and remove everything it finds. But, I would delete all cookies prior to that. Starting with a clean slate may do the job. I have not noticed anything unusual with Yahoo.

 

Avira showed no threats. I ran SuperAntivirus and it showed nothing.
The warning was one of those bogus sites, but it may have infected me none the less. What's strange is I was only on sites I'm familiar w/ Yahoo, this site, stock pages, and weather. I'm wondering if I should dump FF and then reinstall?

 

Decided to try a system restore, which did the trick. Whatever it was, nothing picked it up (that's scary), but it appears to be gone now.
Thx Westside.