Dear customer,
If you have created a real encrypted partition, using Rohos Disk Browser(Portable), try to format the USB drive, using another, not standard Windows software.
If you have created an ordiary rdi-file container, use data-access procedure with rdi1 file from your user account. for more info:
http://www.rohos.com/2008/10/how-to-repair-rohos-disk/#more-160 ,
'Disk recovering' paragraph.