AspUpload的技术文件中有提到：

IIS6.0 prevent the upload of files more than +200Kb.
For IIS6.0 users, the AspMaxRequestEntityAllowed property specifies the maximum number of bytes allowed in the entity body of an ASP request. If a Content-Length header is present and specifies an amount of data greater than the value of AspMaxRequestEntityAllowed, IIS returns a 403 error response. This property is related in function to MaxRequestEntityAllowed, but is specific to ASP request. Whereas you might set the MaxRequestEntityAllowed property to 1 MB at the general World Wide Web Publishing Service (WWW Service) level, you may choose to set AspMaxRequestEntityAllowed to a lower value, if you know that your specific ASP applications handle a smaller amount of data.

Open your metaname.XML which is located in c:\Windows\System32\Inetsrv find the line "AspMaxRequestEntityAllowed" and change it to "1073741824".
You might need to start windows in Safe-mode to be able to change that file, otherwise it's being used by IIS.

Windows 2003 Server中的IIS6预设上传是200KB
必需到C:\Windows\system32\inetsrv资料匣中找metabase.xml这个档案
修改其中的『AspMaxRequestEntityAllowed』设定
预设是204,800Bytes = 200KBytes
2,000,000 = 2MB 以此类推,依您预估需求去调整即可