Facebook is down for my whole network, off and on the last 2 days...

Hi, I would LOVE any help at all, I don't know what else to do.
Our problem started yesterday, with the website never loading, We have 5 computers and my android phone that all use the same wifi. Chrome just tells me the website isn't available. IE tells me "http 500 Internal Server Error." Firefox just says it's timed out. In the afternoon, it loaded again, but then today it's off. I haven't changed anything on our firewall recently that I know of. I've restarted the computer and the router, I ran an AVG scan, and then I checked on multiple websites to see if anyone else reported it down, which they hadn't. I also cleared the browsing history and cookies.

I've ping-ed it, with 4 results of
bytes=32 time=74ms TTL=242
the packets were sent =4, received = 4 lost =0

What else can I do? Please help, my Grandmother is going crazy without it. :)

Thanks,

Brianna
 
Thanks, I am downloading avast right now. I did try that website, and it's not down for everyone else. :) I also discovered that I can access it using m.facebook.com.
 
Contrary to my posts elsewhere in this forum, I am on facebook in Firefox,SeaMonkey & Google Chrome & no problem with the exception of Google Chrome where I had to do this. "you might try logging into your facebook & copy the link then go into the Google Chrome settings Click Show Advanced settings, Privacy>Content settings>Down to Java settings & click Manage Exceptions & paste the url into the Host name pattern then click the allow button & OK."
 
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