IIS Redirect - axd files getting 500 Internal Server Error

Question

The rewrite rule i built returns 500 Internal Server Error for path that contains axd. all other paths works fine.

the rule:

<rule name="isite rewrite" enabled="true" stopProcessing="false">
     <match url="sub.*" />
     <action type="Rewrite" url="http://{MY_INTERNAL_SERVER}:8383/{R:0}"/>
</rule>

everything work's fine but url's that contains axd path fails with 500 Internal Server Error

for example: http://sub.site.com/WebResource.axd?d=VulAtfIQPaLvaSxP9LTeiyvvAmd8FbIf6Q9ixGIpCgSDhZqzJbeu9udOTMbvs9iVhh4fHt3IYOe_Kp2xsAxYVpD0efUoQhQMVWmavqplBDk1&t=636445915058816667