I have some copied systems files i can neither unlock or trash.
Can anyone give me some advice?

if mac - try booting in single user mode, or off of a backup
win - either safe mode, or boot around using bartpe

Problem is it's an external storage (NAS).

I wondered about that after I posted... I assumed you were using the USB interface. Try this from the netgear forum:

http://readynas.com/forum/viewtopic.php?p=150443#p150443

Essentially mapping to the root of the NAS drive as admin - you should be able to deleted and or change file attribs from there

I have a ReadyNAS NV+ and I had the same problem. I worked with Netgear tech support and they could duplicate the problem from the Mac side. They produced a newer version of the firmware so make sure that you have the lastest firmware update for the device.

Additionally, I found out by accident that accessing the ReadyNAS NV+ using WinXP running on VMWare Fusion on my MacPro, I was able to delete the files that I could not delete from the Mac OS. So if you have Windows, either with Bootcamp or emulation software, you could do the maintenance.

Good luck.

Bud James
North Wales, PA