You seem to have a problem with your initial setup. You say your friend has a similar drive? If his drive is not exactly the same model and type, you may have loaded either the wrong drivers or your setup may be wrong.
Note that 250 GB Seagate is not enough information to be exact. There are several types (SATA, ATA, Ultra ATA, etc.). A list of seagate drives and their technical specs are here:
http://www.seagate.com/cda/products/discsales/guide/ As you can see, performance, configuration and even cables may be different. Determine the model and type drive you have and compare it to your friend's drive. Are they the same? If not, remove/uninstall your drive and install the correct drivers. This is a good idea regardless.
Installation wizards, drivers and other tools are available for free download from the Seagate Support Site here:
http://www.seagate.com/support/disc/utils.htmlCopy/backup any files or information you want to save before you reinstall.
You will need the info above and your operating system.
If you have any trouble with the procedures or need further help, let us know.
Dell