关于使用struts2上传ppt

我上传的是ppt文件，后台报错Content-Type not allowed: file "upload__19f45d3d_131d360abad__8000_00000002.tmp" application/octet-stream

struts.xml配置：
<action name="upload" class="com.test.action.UploadAction">
<result>/uploadResult.jsp</result>
<interceptor-ref name="fileUpload">
<param name="maximumSize">409600</param>
<param name="allowedTypes">
application/vnd.ms-powerpoint
</param>
</interceptor-ref>
<interceptor-ref name="defaultStack"></interceptor-ref>
</action>

ppt的文件类型是application/vnd.ms-powerpoint
你实际上传的是application/octet-stream
检查一下上传Jsp文件