Call to .axd returns 404

I created my own .axd handler for uploading file and set everyting in the web.config.

when I call the .axd, I get 404.

I have another .axd which works fine on the same web application.

in httpHandlers I have:

<add verb="GET" path="ShowImage.axd" validate="false" type="ImageServer.StreamImage, ImageServer"/><add verb="POST" path="UploadFileServer.axd" validate="false" type="UploadFileServer.UploadFile, UploadFileServer"/>

in handlers (for iis7) I have:

<add name="ImageServer" preCondition="integratedMode" path="ShowImage.axd" verb="GET" type="ImageServer.StreamImage, ImageServer"/><add name="UploadFileServer" preCondition="integratedMode" path="UploadFileServer.axd" verb="POST" type="UploadFileServer.UploadFile, UploadFileServer"/>

ShowImage.axd works fine, UploadFileServer returns 404.

why?