Hard drive not recogized in my computer or disk management

hi i am new to this and 18 about to go to uni next week so i need some help and FAST! i bought a 320gb hardrive in june 2010 and it was perfect i made a back up of my whole HP system. However a friend of mine plugged my hardrive into her apple mac and i think my hardrive must have synced to her hardrive called time machine or something like that and now i am trying to use my hardrive in my hp laptop it wont work.

ive tried everything it wont show my computer i searched for help all over the net and with technicians on the phone saying to go into disk management and its not there either. One techinician was sayin i might have to reformat it on the mac.

this cost soo much money and i cant afford to buy another one nor can i afford to lose all my data on this one..

please is there a genius out there that can help me!!!!!!!!!!! :(


Posts: 3,357   +116
Timemachine shouldn't automatically synchronise to the hard drive, unless told to do so. Also, in order for time machine to function on that drive, it requires it to be formatted in the MacOSX native filesystem.

In case your not aware, Timemachine is Apple's backup software, designed to backup Apple systems.

If the data on the hard disk is not of any consequence (e.g. it contains no essential data), it can be formatted as NTFS, which will then be read by Windows. Unless it has been formatted as a Mac OSX partition it should be read natively anyway. In other words, it should be NTFS still.

Lets go back to basics:

1. If it's an internal hard drive, does BIOS identify the hard disk?
2. Your positive disk management doesn't identify the hard disk?

You could use a bootable partition editor like GpartED to boot from the DVD drive and inspect all your connected partitions.

You could also boot from a Linux Live distribution like Ubuntu as well, which would enable you to check your connected partitions/drives.

The fact Windows is refusing to identify that hard disk is leading me to suspect its been re-formatted as a Mac OSX filesystem and as such can't be read from Windows. If its been re-formatted your data is already lost, in which case just formatting it will resolve your problem.


Posts: 6,429   +186
Hi jammogirl

I'd like to add a few questions / comments along with Leeky's

1. First, as Leeky asked, it's important for us to know if this an internal or external hard drive?
2. If i had to guess, i'd guess it's an external USB drive?? but please confirm if so and tell us the make/model if you can

Also, see this thread Comp can't detect new hard drive

As in your case, as well, we want to follow "the Windows trail"

Looking for the drive in the following order: from BIOS => Device Manager => Disk Management => then finally My Computer and Explorer

tho BIOS doesn't apply if it's an external drive

And what we look for in Device Manager can also vary between internal and externals

so if you could answer above questions, we can then go the next steps


Posts: 1,020   +56
External HD in MAC format?

Hi all, This sounds like it's a USB powered external HD, sizes are 250,320 and 500 GB (Western digital Passport?) If it was used with Windows as a backup for files, I would have thought the Mac would not have been able to read it. If the Mac has damaged it, or re formatted it, then most likely all is lost (to Windows) unfortunately. One slight hope I can think might work, is if the Mac user installs some data recovery software, (some free programs do exist,) then text from documents might be recovered.
Also jpeg photos could be saved by same method. It would also be worth plugging it into another Windows PC just to check if there was a problem with the first PC.