Can't read my Buffalo mini station HD-PF250U2/BK-US

SOURCE: time for physical format ???

Formatting such a large hard disk will take a long time, especially if you do a full format (not a quick format).
Just let the computer do its thing, don't turn it off.

SOURCE: time for physical format ???

Did you fit the drive into the Buffalo drive case? If so, take it out and put it in your computer tower/case and format it from there. Then put it back into your Buffalo case.
Go to the Buffalo sight and see if your Drivestation needs a firmware update - there may have been bugs in the one you purchased.

SOURCE: External Buffalo Hard Disk 500 Gb model no

Check the usb port function in the computer bios settings and be sure that it is set to yes. Connect properly your external drive. If it has two wire usb connections, use both to obtain the maximum power that will be need by your drive.

SOURCE: Can't access Buffalo HD-HB250U2-WR 250gb Ext. Hard

I think I have the answer, plug your cable in. If windows 7 shows the message unknown device don't remove the usb. instead turn the switch on the back of the external hard drive off for a few seconds then back on. Windows 7 should then for some unknown reason find the correct drivers and your buffalo hard drive will now work. This worked on mine.

Cliff
hotdesignerwear.com

SOURCE: When i connect Buffalo Mini

An external storage-device has four major components:

* the USB cable

* the power-adapter

* the disk-drive inside the enclosure

* the USB-to-disk-drive adapter inside the enclosure.

One of these components has failed.

Try a different USB cable.

Try connecting to a different USB port on your computer.

Try connecting to a USB port on a different computer.

Take a "multi-meter" and measure both the voltage and amperage output from the AC adapter, and compare with the specifications on the label on the adapter.

Open the enclosure, and remove the disk-drive, and then connect it as a "slave" disk-drive in a desktop computer, to see if it works at all.

Purchase a new, compatible, disk-drive, and install it in the enclosure, to "revive" your external storage device.

Get the part-number and serial-number from the label on your disk-drive, and access the manufacturer's web-site, and use "check warranty status", to see if they will replace the device, at minimal cost to you.

There exist commercial "data recovery" services that can try to repair your device, just long-enough to rescue and copy your files.
For example, see: https://services.seagate.com/index.aspx?lng=en-US for a "no data - no charge guarantee".