My web page is located at maxpavlov.com/interesting/fileupload/
Can I use URL Rewrite module in IIS to have a user address bar show file.maxpavlov.com
every time he visits the aforementioned url?
URL Rewrite can't change the URL displayed in the address bar, per se. However, if you linked to file.maxpavlov.com (rather than maxpavlov.com/interesting/fileupload/), you could use URL Rewrite to rewrite that request to maxpavlov.com/interesting/fileupload/:
<rule name="CustomRule" enabled="true" patternSyntax="Wildcard" stopProcessing="true">
<match url="file.maxpavlov.com" />
<action type="Rewrite" url="maxpavlov.com/interesting/fileupload/{R:0}" />
</rule>