By default the Sharp copier will apply the reply email address as the filename when scanning. To stop this from happening see the below screen shot.
Log into the mfp via a webpage using the mfp's IP address.
Open Application settings, you maybe asked for the admin password which in this case is admin.
Choose Administration Settings, and uptick Sender Name. Now click on Submit at the top. Now when you scan it will just have the date and time as the filename.