Knowledgebase: Android with TouchDown
You cannot add an attachment while the device is connected to a PC
Posted by Donna Magada on 24 February 2010 03:12 PM

You are unable to add an attachment to an email while the device is connected to a PC via a USB port.  While the device is connected, you are unable to view files or folders on the device SD card, therefore making it impossible to select and attach a file.

In addition, there is no error message suggesting that you disconnect the device in order to view the files.