what image you try to flash, you sure have ORIGINAL Dreambox 8000?
Turn off antivirus/firewall
DreamUp/JapharFlasher set Bad Sector Recovery and flash again
benutze einen anderen Browser, versuche es mit Firefox Portable 3.5.1
Try to reset the bios settings:
Connect the serial port, use a terminal program as Putty or from windows the Hyperterminal.
When connect and turning on the box, press the S key to go to the Advanced setup (bios) utility.
Or press the front button, turning os the box may also give you the Advanced setup into the Terminal screen.
Goto the Exit tab and choose the Reset all settings to factory default.
This you can also preform with optiflasher.