今天在用FCK，在超链接-->上传-->发送到服务器中
报Invalid Request错误
找了半天才找到，解决如下：
I had this problem as well. The problem is that it can't find the type of resource for upload. I assume that it should detect the resource type by file extension, but there is no code to do that.
I fixed it by adding the resource type "File" in the config. I think this is a workaround, but it worked for me.
So the link browser url looks somewhat like this (added Type=File&):
FCKConfig.LinkBrowserURL = FCKConfig.BasePath + 'filemanager/browser/default/browser.html?Type=File&Connector=http://www.cnblogs.com/http://www.cnblogs.com/connector.' + _FileBrowserExtension;
And the quick upload looks like this (added + '?Type=File' ):
FCKConfig.LinkUploadURL = FCKConfig.BasePath + '../upload.' + _QuickUploadExtension + '?Type=File' ;
翻译过来就是：在fckconfig.js中，找到FCKConfig.LinkBrowserURL那一行
改成下面这样：FCKConfig.LinkBrowserURL = FCKConfig.BasePath + 'filemanager/browser/default/browser.html?Type=File&Connector=http://www.cnblogs.com/http://www.cnblogs.com/connector.' + _FileBrowserExtension;
找到FCKConfig.LinkUploadURL那一行，改成：
FCKConfig.LinkUploadURL = FCKConfig.BasePath + '../upload.' + _QuickUploadExtension + '?Type=File' ;