Hard Drive Automatically Hides on Restart


New Member
I have 7 pro x64. I have one hard drive I use to run windows from, along with a secondary one used to store data. Every time I restart the computer, the secondary hard drive gets hidden. I use Easeus Partition master to unhide the drive. It works perfect until I restart again.

I have tried changing registry settings on hiding hard drives, along with the typical built in windows methods to hide/unhide a hard drive.

Does anybody have any ideas on what is causing this??


Microsoft MVP
Staff member
Microsoft MVP
Go to control panel, admin tools, computer management, storage, disk management and compare the properties for each of the two drives.


Honorable Member
Is it a secondary HDD or a second partition of the first disk? Is it just losing the drive letter? Have you tried making it appear by assigning it a new letter?

You can try to use the free Easeus Partition Table Doctor http://www.ptdd.com/

There is also a solution from Microsoft:
When you resume a computer from sleep or from hibernation, the SATA hard disk drivers require the SATA hard disks to be ready within 10 seconds. However, a large SATA hard disk may take longer than 10 seconds to be ready. In this situation, the resume operation times out.

Here is the link to the HOTFIX:
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