November 3, 2010 § 2 Comments
Few days ago I encounter the HTTP error 412.
It’s so weird that I uploaded few JPG files without error, except one which is JPG as well.
After I exported to PNG , it works again.
Got tips from a friend as following.
This is caused by mod_security, which is used for blocking spam , but sometimes it got triggered by accident.
For quick and dirty fix, you could edit your .htaccess. and add following
And if you are interested about the issue, you could look at following link
In summary, the mod_security will determine if the request is spam by looking at the URI / POST.
For URI like “-poker” or “-sex”, mod_security will be triggered and blocked visiter to execute such action.
In long one, one should not disable the mod_security as it provides minimal protection from spam. Starting looking at the URI or POST that might trigger the mod_security and add following lines.
In our case
SecFilterEngine On SecFilterSelective "POST_PAYLOAD" "KEY WORD" "allow,nolog"
replacing the keyword with the one you think may trigger the mod_security. I think this is a better practice at last.