What you mean 'not found'?

grrrrrrrrrrrrrrr

You can either apply that to me thinking that attaching a file to my InfoPath form would be easy or MS for allowing such a nasty insidious bug to crawl out into production.

Here's the issue. I have an InfoPath form running under MOSS Enterprise forms services. Upon this form I have a couple of file attachment controls. One would thunk that given that file attachment controls seem to have been a part of HTML since the mid 1990's  that this should be a totally elementary operation.

Heh, think again.

I found this out the hard way when, after browsing to my file and pressing the Upload button I was met with a rather curt 'The Selected File was not found' error message.

here is sol'n Add the attribute enctype="multipart/form-data"  to this tag and save.

I haven't really found a suitable solution / explanation for this, but there is a workaround. You can edit the html where you are using InfoPath add the following javascript code into the file:

<script type="text/javascript">
aspnetForm.encoding = "multipart/form-data";
</script>