No, that is not necessary for the file to upload, but since you did not give me a specific direction to look in, in other words mention that upload doesn't work at all, I just mentioned the problem i did see.
if the upload is not working at all, try these steps to begin troubleshooting:
1) Edit the update record server behavior, clear the redirect option.
2) Add the following code at line 1:
3) open the bindings panel and expand the WA Uploaded Files Global Status group.
add the debug info binding to the page.
post back the results after trying an upload test.