flash memory mandrake 10.1 dell latitude cp
 

cant see the usb flash memory on hardrake or dmesg.

When you insert the memory (we are talking about a USB pen drive ?) it will probably appear as a device under /dev/sda1 (or /dev/sdb1, /dev/sdc1 etc...). Just mount the device it after plugging in.

mount /dev/sda1 /mnt/pendrive
(assuming that it's on /dev/sda1 and that you have already created a folder /mnt/pendrive)

If I'm completely wrong about what you are trying to do, please give lots more details !

well, I solved the problem, you have to plug in the usb flash memory before the instalation, otherwise my laptop wont recognize it.