Hello !
as I couldn't access either with DCC or Filezilla on my USB Key , I've used gorski suggested " mini tool Partition" , created 2 partitions on the usb key , one in Ext4 the other in FAT 32 ,
put my PICON folder on FAT 32 and Flashextension and swapfile on Ext4.
Everything works perfectly now !
Thanks at both of you !!!