Does anybody recognize this USB chip?

Searching SMI show it is Sun Microsystems, Inc. Does it hold anything important? If not, you can try to format it with NTFS in Disk Management or Partition Wizard free.

GokAy, only with the Removable Disk 1,78GB I can do what ever i like, format, etc, without any problems.
But I want convert this U3 behaviour and tricky device to a normal USB device so I can use the full 16 GB capacity again. The CDFS readonly part that contains the old, obsolete software is not listed in diskpart. Probably I have to use a kind of small utilility who can do this wiping. But there are so many different utilities. Maybe someone can help me pointing in the right direction? Many thanks and regards, Robert

Ok, try the tools listed here: Restore Your USB Key to it's original state | USB Pen Drive Linux bootice link gives 404 for me
Bootice here Download BOOTICE 64-Bit - MajorGeeks

If those fail, you can try imageusb Tools for OSForensics - ImageUSB - Write an image to multiple USB Flash Drives

GokaY. Thanks for your suggestion. I tried all. The first tools only recognize the removable disk. The other volume is still recognized as CD drive even under Linux. With the last tool ImageUSB it says imaging failed when selecting the CDFS volume.

Yea, CDFS means it's a U3 drive.

To my knowledge you can't reformat a U3 drive unless a utility to do so is provided by the manufacturer. For example, SanDisk provides tools to you switch back/forth between U3 and regular drives for only some of their devices. Many (most? IDK) manufacturers provide no such option at all

The device firmware won't allow that "CD" to be overwritten