Hard Drive Partitions Disappear

I have a Windows 7 PC with 2 physical hard disk drives on it. The first drive has 2 partitions (C, D) and the second also has 2 partitions (E, F). OS is installed on C.

Recently I started noticing a strange behavior. 3 of the 4 partitions (D,E,F) become unavailable (not visible in My Computer, and I am not able to access them by entering an address like D:\ in windows explorer). However, the drives become available again once I restart the system only to disappear again after some hours of use. Both drives also show up in BIOS.

I am guessing it is not an issue with the physical drive since partitions on both physical drives are affected. I have done a drive scan and a virus scan using Symantec Endpoint Security on all drives without much luck.

Any help in resolving this issue will be much appreciated, please.
 

jobeard

Posts: 13,970   +1,778
How is the 2nd drive physically connected? Do you have a Power Plan which shuts off the HD after X amount of time?
 
  • Thread Starter Thread Starter
  • #3
How is the 2nd drive physically connected? Do you have a Power Plan which shuts off the HD after X amount of time?
Both drives are connected internally (SATA). The system is a HP Z800 workstation. The second drive is a 1TB Seagate drive. No. There is no power plan that shuts off the HD. Actually, in a bid to resolve the issue, I set the hard drive shut off time to 100000 minutes.
This system has worked just fine with both drives for more than a year now. I started noticing the hard drive shut down issue about a month ago.
 
Hi there,

Have you checked if the partitions are listed in Windows Disk Management when they disappear from Explorer? Another you could do is go the Device Manager and right click on the Disk drives and select scan for hardware changes. Does that make a difference? Have you installed any new hardware/software lately? Keep us posted.