HP Microserver Gen8 won't boot from USB key (CentOS & Ubuntu Server)

[Aljoscha]

Hi!

I try to install CentOS to the HP Microserver Gen8. With the external DVD-drive there are some problems (I/O-Errors, bad blank DVDs). So I tried to install the OS with a bootable USB key. But after selecting F11 (Boot Menu) -> One time boot from USB key, the server complains that there is no OS.

I've tested it with CentOS and Ubuntu Server. Same result. When I put the USB key to another PC, Ubuntu/CentOS-Installation is started.

I plugged the USB key into one of the front usb sockets.

Where is the error? Please help!

Thanks a lot

Aljoscha