Network problems knocked more than 10 million WordPress blogs offline in a two hour outage on 18 February.
WordPress.com said the problem was caused by a core router change at one of its data centre providers which "broke the site".
The company estimated that during the outage, the blogosphere lost about 5.5 million pageviews.
WordPress.com founder Matt Mullenweg said it was the firm's "worst downtime in four years".
"I know this sucked for you guys as much as it did for us ? the entire team was on pins and needles trying to get your blogs back as soon as possible.
"I hope it will be much longer than four years before we face a problem like this again," said Mr Mullenweg.
On the company blog, he stressed that security was not an issue and that the site had not been hacked or hit by a denial of service attack.
"All of your data was safe and secure, we just couldn't serve it," he wrote.
Mr Mullenweg said the company would dig deeper to discover what happened and work out a better plan of how to cope if the problem recurs.
Full story here
http://news.bbc.co.uk/1/hi/technology/8523323.stm