Windows 7 64bit does not recognize my 1Tb external drive

Hi,

I've been all over the net trying to resolve this issue, and found many hotfixes, downloads from Microsoft and manufacturer, but to no avail.
My external drive was recognized for the first month. Then, very suddenly, Windows 7 doesn't recognize it. It sees it, but prompts a "Need to Format before first use". It has 300G already used with valuable info.
Tried moving the external hard drive to our home PC with Windows XP and the same "Need to Format" message is prompted. If I hook it up on my wife's MAC, I can see the data.
Now I have read that this is a known issue with the 64bit version of Windows and external drive. I have already all the KB976972 and KB977074 download fixes from Microsoft. I have also tried to uninstall the drive, unplug it, turn it off, restarting Windows, and plugging back the drive, but I have the formatting prompt again. And if I choose to not format, i have an error message DATA ERROR (CYCLIC REDUNDANCY CHECK).

**This does not seem to be an issue regarding only the WD drives but all drives**

Called WD tech, and it was useless.

Does anyone have a fix? A link to share? An idea? I'm running Windows 7 Ultimate 64bit on my HP Pavilion a6418f.

Thanks for any help...!

E.

Wish I had answers, but am having a similar problem, so I thought I'd add another data point. I have 6 each 1 TB WD Passport drives (usb 2/3 models). Drives with only a small amount of data (well under 300 GB) can be read/written with no problems on my Windows 7 Ultimate 64bit. This is true both through my USB 3.0 card and my USB 2.0 internal system. The drives with a lot of data (600-800 GB) simply get the "drive not formatted" error, if they are seen at all (2/3 are seen and give this error, one comes and goes). On the plus side, for myself, the Windows XP laptop I have access to has no problem reading the exact same drives.

Two of the unreadable drives were written to from a UNIX box (but with NTFS), which I originally thought was the issue, but the same behavior happens with drives that never touched a UNIX box. I have also been digging on this for a while with no resolution.

So, the drives are clearly formatted NTFS. Seeing them from Windows 7 is what appears problematic. A weak correlation seems to be that the more data on board, the worse the problem is.

A completely different 3TByte (larger form factor) Seagate drive with external power does not seem to be having any problems, USB 2.0 or USB 3.0.

Just a couple more data points to consider. Thanks!

I go to the WD forums a lot and there are problems it's just a user forum. Did you always remove the drive properly? Not doing so might corrupt the drive. Did you use this on multiple computers? Does it show in Device Manager or Disk Management? If it shows in Disk Management what does it say? If you need the data off it there might be a problem with it being read only on the Mac. Look on Apple and find NTFS 3-G and install on Mac the you should be able to access data OK. There are some things you can try once the data is safe.
Joe

Originally Posted by Joe S

I go to the WD forums a lot and there are problems it's just a user forum. Did you always remove the drive properly? Not doing so might corrupt the drive. Did you use this on multiple computers? Does it show in Device Manager or Disk Management? If it shows in Disk Management what does it say? If you need the data off it there might be a problem with it being read only on the Mac. Look on Apple and find NTFS 3-G and install on Mac the you should be able to access data OK. There are some things you can try once the data is safe.
Joe

For myself, the drives are fine. I can open/view them on the XP laptop with no problem. On Windows 7, they just appear unformatted (or don't appear at all) in disk manager, and appear correctly (again, if seen at all) in device manager as the right device. For what its worth, I am leaning toward a power issue, however why it is worse with Windows 7 than XP (as it appears to be from other threads) I am not sure, and the other symptoms are nuts. Could be that they are doing some additional power management or something now. Could also be the chipsets are more sensitive in the newer systems. Again, this does not explain all of the symptoms.

I see now that there is a long thread that has been fighting with similar issues.... Also, I'll be trying it with an externally powered USB 3.0 hub this evening.

Thanks!

Is this a powered or USB powered drive? For the USB powered drives they make a power booster cables. Another thing on USB powered drives a lot of PC's use pretty wimpy power supplies and the constantly expanding number of devices using it for power. Sometimes the Ports in the back of the tower work better too. USB 3 is so new a lot of machines really aren't able to use it that well even they supposedly are capable.
Joe

BACK UP YOUR DATA!!!

I will say that again.

BACK UP YOUR DATA!!!

Ok, now that I've stated the obvious, onward with more fixes. First off, i just installed a brand new drive tonite myself. When creating partitions for it, I was asked if I wanted an MBR, a Master Boot Record or a GUID, which I forget. The interesting part was that it reported that drives over 2Tb cannot be seen with an MBR, but have no problems with GUID. The drive I installed tonight was only 1.5Tb. I used GUID anyways. Do you know how the partitions are lain on your drives? This could have something to do with it.
BACK UP YOUR DATA!!!
WARNING!!! WARNING!!! WARNING!!! The below steps WILL remove any and all data from your drives!!! WARNING!!! WARNING!!! WARNING!!!
Once that is complete, I recommend removing your partitions, then re-adding them with GUID as the layout, not MBR. Then perform a quick format with NTFS.
WARNING!!! WARNING!!! WARNING!!! The above steps WILL remove any and all data from your drives!!! WARNING!!! WARNING!!! WARNING!!!
Copy your data back over to the drive. Use as normal.

I have been having issues with Windows 7 on three different machnes not recognizing ext hard drives that were formerly recognized. Oddly, the drives can be seen in Disk Management but not with the correct labels I assigned. I read a fix online that suggested re-assigning a drive letter to the ext drive and voila! now Windows sees the drives ..however, all the folders are reported as "shortcuts". Great, so doing a 3 hour chkdsk to see if this fixes it.

Thanks to the fellow who cries "backup". As an old tech I cry the same to my customers. However, I will add one caveat "Backup to two or three or FOUR locations" or you will be crying a sad song. What good is a backup to external media that suddenly Windows does not see?

To expand on what Viajerozz said, I was having the same problem described but with a small twist. I was able to see my 1TB external HDD (internal in a powered external case) with my 32bit Window 7 laptop but not with my 64 bit Windows 7 desktop. After seeking the advice of Google, I ended up realizing that the disk was visible in Disk Management, but not in Computer (formerly My Computer). Disk Management >> right click drive >> change drive letter and paths >> add >> select whatever drive path you would like and I was good to go, all 931(real)GB were visible and accessible. Hope this helps some poor Googling soul sometime in the future.

Originally Posted by Viajerozz

I have been having issues with Windows 7 on three different machnes not recognizing ext hard drives that were formerly recognized. Oddly, the drives can be seen in Disk Management but not with the correct labels I assigned. I read a fix online that suggested re-assigning a drive letter to the ext drive and voila! now Windows sees the drives ..however, all the folders are reported as "shortcuts". Great, so doing a 3 hour chkdsk to see if this fixes it.

Thanks to the fellow who cries "backup". As an old tech I cry the same to my customers. However, I will add one caveat "Backup to two or three or FOUR locations" or you will be crying a sad song. What good is a backup to external media that suddenly Windows does not see?

Hi, did you ever find a solution to this? I'm experiencing a similar problem.