First off, it's not always good to swap proprietary drives & cases. Hp more than likely has the drive (now in your laptop), set up to work with their case. Kind of like Apple did with the Hitachi micro drives after they found out you could use the drive elsewhere.
What's the age & OS of your laptop? But more importantly, you probably need to look up hacking Seagate drives. Or reverse engineering them to work in HP cases.
Not all drives are interchangeable to all computers. Proprietary computers & computer companies (HP, Gatway, Dell) keep close tabs on their stuff & make it more difficult to upgrade. That is, they don't play nice with others.
The only deal that comes with one, is the initial price, after that you pay for it. I used to charge extra because they were so different.
That's my thought on it. Try the HP website (don't get mad if they tell you to go away) & see what other drives they use in their cases & laptops. See if maybe you can find a patch for the swap. Or if there is a code, switch or such that you need to use or take off the other drive. They make very good products (overall), but they only want their parts used.
Additionally (back to OS version). If your laptop is less than XP it won't be able to read NTFS. If it is, reformat to FAT32 for ME FAT for 98/95.
The write protection may be the "block" HP puts on the drive.
Good luck, let us know how it goes.
i have an HP external hard drive case (i used the included 500gb drive as my laptop's internal hard drive) that was housing a Seagate Momentus 250gb drive. The drive worked perfectly when installed as my original internal drive (with OS), but whenever it is connected as an external, it is only shown as a CD drive, and windows will not read from it...
i then formatted the drive (again as an internal), and it is now a single NTFS partition. my laptop still shows it only as a CD drive and will not access it. it IS listed in the device manager as an HP hard drive, so i populated the drive. i then tried to initialize the drive through disk management- but windows then states that the "media is write-protected"...
any suggestions??

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