Wow, typical repair shop. They have no idea what they're doing and remove the OS restore partition. You have no idea how many times I've seen this.
Anyway, it appears a manual reinstallation is required (thanks, repair shop). Since the MD partition is still there, this shouldn't be too hard.
http://support.dell.com/support/topics/global.aspx/support/dsn/en/document?docid=179256
Removing bitlocker is not hard. You do not need the diagnostic partition. The diagnostics can be run from the resource disc or a flash drive.
The last time it was turned on it booted to MediaDirect w/message Building Your Dell Media Direct files.
Then the message cannot access your HDD may be because you may have enabled MS BitLocker comes up with an exit button which shuts down the laptop.
Restarting the computer returns you to MediaDirect again.
This is my Neighbors laptop. She has never used MediaDirect or enabled the BitLocker.
There is no diagnostic partition on the HDD. A repair shop wiped the HDD and reinstalled windows XP Home about a year ago.
I removed the HDD and booted the laptop. MediaDirect did not come up, until I reinstalled the HDD.
If the Owner did enable BitLocker, what to do?

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