The instruction here shows how to copy the attachment from email to USB disk via iUSBport2
1.) Download the attachment from email and then open up the file.
2.) Tap the "Open In" icon ( upper right corner), and select "Open in iUSBport"
3.) The file is saved in the iUSBport app > Local > UDMA2 Presentation.pptx
4.) Power up the iUSBport2 and plug in the USB thumb drive or external USB storage device.
5.) Connect the WiFI on iPad/iPhone to "iUSB2-xxxx"
6.) It might go to the Log In page, please tap "Cancel" and reconnect the WiFi to "iUSB2-xxxx"
7.) The second time in Log in page. please select "Use Without Internet", and the connection will be stable.
8.) Open up the iUSBport app on iPad/iPhone, it is a free app from the Apps Store: https://itunes.apple.com/us/app/iusbport/id581463199?mt=8
9.) Tap the "iUSBport2-1" and go to the " Local " where the file is saved.
10.) Tap the "Edit" on the upper right corner and select the file to be copied. A Red check mark is on the selected file.
11.) Tap the Menu key and select "Copy"
12.) Go to the Dashboard in step 9 and tap "iUSBport2-1", select the "C" drive which is the attached USB drive and hit the Menu key for Paste.
13.) The selected will be copied to the attached USB drive.