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Windows 7: WIERD -- GPT NTFS 3TB HDD issue

31 Oct 2016   #1



Had a small power outage (no more than 1/4 sec) Desktop shutdown (bios setting) I restarted but failed to boot - unknown OS or some such msg.

It is a 3 HDD duel boot Win7-64/Win10-64, OS are on diff partitions - diff HDDs.

After the power outage, Somehow Win7 was lost to the boot up, could boot to Win10 via repair disk method, tried restart repair 6 times on Win7, I tried easybcd, diskpart & other shell techniques, minitool partition, paragon partition, and so forth. (you know how it is you try stuff for hours)

I got the idea to try AHCI/EFI rather than MBR/IDE to see if it did any diff - no go - tried some tools in this mode. (** Did this I mess things up?)

FORCED Win7 working by removing 2 of 3 hdds but the Win7 install HDD, of course forcing the MBR and so forth.

I added a new, 2nd 3TB GPT disk, into system and copied non OS stuff from older replaced disk onto it (to replace a 750gb w/ 3TB). Things work fine - both Win7 & Win10, which I ended up re-installing Win10-64 to 1607/Anniversary on same HDD as Win7- Win10 is my backup OS.

Now 1 old disk w/ Win7 & Win10 ONLY, 1 New 3TB GPT hdd w/ lots of stuff - 2 partitions - 1 128mb partition - 2nd partition remainder.

*** Now Here's the Problem ***
Add #3 HDD!

I added my 1 yr old 3rd HDD, a 3TB GPT 2 partition disk - main partition of 'stuff' - small 128mb partition - remainder 2nd partition.

Booting to Win7 or Win 10, this #3 HDD is unknown via windows disk manager !!
This HDD is a 'NTFS GPT EFI system partition' - shown by minitool & paragon partition tools, the other FULLY functioning GPT 3TB disk is a 'NTFS GPT data partition' partition.

Oddly last night using the above tools along w/ diskpart and other shell tools - trying anything I could & found suggested via searches, the 3rd HDD (O:) got somehow 'visible' to Windows fully, both Win 7 & 10 - restart NOT a shutdown reboot between !!

BUT !!! After a shutdown last night, now it is NOT visible again (2 hdd show 1 does not).

Here's the Wierd thing - if I hide the partition via shell OR partition tool, then UNhide the partition - it does not show in explorer BUT, if I use a shortcut to a directory on HDD #3 - IT IS WORKING AND THERE !!!

But windows explorer does NOT show the Label '3TB-O' just 'O:' so it is not 'really' there - if I refresh explorer 'O:' disappears - but if I shortcut to it again, it re-appears, repeatedly !!

I seems normal in use, when there - windows disk manager still does NOT see it !! Can copy and access files perfectly!

So I need help!! WIERD !!! PLEASE HELP ME FIX THIS !!!

My System SpecsSystem Spec
31 Oct 2016   #2

Why did you move this - NOT a h/w issue - a s/w issue !!

It is NOT a hardware issue at all, h/w works fine - it is a partition type or partition table or some other wierd s/w issue.

You think it is best here ?? It was caused by a startup issue via typ M$ software startup corruption non sense !!

Help Please ?!
My System SpecsSystem Spec
01 Nov 2016   #3

Windows 7 HP 64

Please edit your profile and add all hardware information.

Go to Disk manager, enlarge the columns, and, with sniping tool, take a snapshot of the screen and post it here as an attachment 9 (Go advanced - Mange attachments - browse - upload).
My System SpecsSystem Spec

02 Nov 2016   #4

Windows 7 Profession 64-bit

Had a small power outage (no more than 1/4 sec)
FTR, that is a long power outage! The ATX Form Factor standard requires all ATX PC power supplies maintain output power during a power outage for no more than 17ms (milliseconds). 1/4 of 1 second is 250ms. The best we humans can "see" (typically as lights "flickering") are outages that last ~30ms or longer. This means our computers can come crashing down (hard!) due to power outages we, as humans, don't even realize happen.

This matters because sudden power outages, and the surges that typically occur when the power comes back up, is really hard on electronics. But even if the hardware is unscathed, sudden crashes can corrupt drives - a real problem with boot drives that can certainly affect operating systems. But you really cannot blame the OS. If someone runs a stop sign and slams into your car, it is hard to blame your car maker if your car no longer runs.

Note further use of a corrupt drive can result in further corruption too. And you've been using them a lot and running a bunch of different tools on them, without success.

When you are able to get the drives/partitions to reappear, can you see your files? If you don't have a current backup, I recommend you concentrate on backing up anything you don't want to lose before you make any further changes and/or there's further corruption that makes backing up impossible. This may mean pulling your drives and temporarily attaching them to another computer, then copying off the files.

Because it seems some settings in the BIOS are being affected too, I might also look at replacing the CMOS battery.

Beyond that, I agree with Megahertz07 and we need more information.

I would also suggest you start looking around for a "good" UPS with AVR.
My System SpecsSystem Spec
02 Nov 2016   #5


You missed the point which I stated fully, my bios setting is that if power glitches, it powers down the pc NO restart - the best for ANY electronic thing IMO.

And it did just cease running - shutdown!, I was sitting at the keyboard.

And ALL HDD have been working fine, even the one that is at issue - as I said I think it is a S/W issue NOT a h/w issue - thus my disagreement with sticking it in this forum subgroup !!

So no tools/settings/command suggestions ANYONE ?

Re-Read my OP.
My System SpecsSystem Spec
02 Nov 2016   #6


Just uploaded various views of HDD arrangement - note the diff GPT/NTFS config of the 2 GPT 3 TB hdds via Paragon images.

This I believe is the issue not a h/w problem but this differing types of the GPT partitions - basic data vs EFI System !! The other diff is the 128mb partition, the good one is unformatted/raw or something, the 'bad' one is NTFS (originally bad when was trying to use the older 3TB as a boot disk - did not remove the 128mb partition)

Now can someone tell me how to alter the 'bad' GPT hdd to be a good soldier !!

PS: These images are of when I can access the hdd after using the 'hide UNhide' trick using
minitool tool.

Thanks for any Help !!!!
My System SpecsSystem Spec
02 Nov 2016   #7

Windows 7 Profession 64-bit

You missed the point which I stated fully, my bios setting is that if power glitches, it powers down the pc NO restart - the best for ANY electronic thing IMO.
I didn't miss any point. Nor did I say anything about NO restart - which is NOT always best, BTW.

My point was, you have tried stuff for hours, including changing out hardware and changing hardware settings. And you have had drives come and go. Drives coming and going often are caused by changes in the BIOS and changes in the BIOS can occur due to a weak CMOS battery. Now you can waste more of your time by not complying with Megahertz's request, and not swapping out a $2 battery that will (1) ensure you have a good battery and (2) reset any wayward settings in the BIOS/CMOS. It's up to you. We are only here to help you help yourself.

Oh, and there are many cases where having the computer restart is the better choice - remote servers or remote mission essential computers, for example.
My System SpecsSystem Spec
02 Nov 2016   #8


No drives failed at all, just the typ M$ MBR issues, so going to a single HDD allowed me to get system up and running - M$ does not seem to be able to handle a duel boot multi-hdd system at all for repairing the MBR !

That was my case! NO bad HDD!

Was an opportune time to switch in a new 3 TB disk to replace a 750gb hdd that I had been delaying, and since Win10 is a backup OS, just did a new install. No bad HDD!

So tell me how does the BIOS dictates to Windows what the HDD and partitions types are, Windows does not seek this out itself, surely it does as you can change things and see it immediately not via BIOS ?

The partition types are I am almost certain is the issue, Windows is confused - but I have no tool (w/o deleting the full of files partition) to fix things - THUS the quest to get someone WHO MAY KNOW how to fix this.

So I do not think either the BIOS or the battery is the cause of my CURRENT issues - but I may try a back BIOS image - my MB has that - that worries me more than finding a possible other way to deal with this.

PS: I did a chkdsk last night on the HDD and explorer saw the hdd just like normal, but it went away after a shutdown.

I will try a chkdsk again.
My System SpecsSystem Spec
02 Nov 2016   #9

Windows 7 Profession 64-bit

No drives failed at all
Okay - but note I never said anything about drives failing either. I talked about corruption, which can include the tables, not just files.

It seems apparent you are taking your own course of action regardless what any one suggests. So good luck. I really do hope you get it sorted out.
My System SpecsSystem Spec
02 Nov 2016   #10


I interpreted your 'drives come and go' as go bad. The hdd of interest does not come and go unless I do something such as 'hide & unhide' otherwise it is there but NOT there according to Windows - BIOS sees it fine - always !

So what is your 'hard' suggestion ? Battery and BIOS ?

Can you explain how the BIOS tells windows the hdd type and partition type ? Is that not in OS domain ?

My BIOS does not show any real info during boot other than the disk/DVD/ram it finds - no mention of HDD types or partitions - does yours ?

I am sorry but I need to understand before I do something that may mess things up - I think as I said in OP that maybe my AHCI BIOS change and boot attempt (did not boot) may have done something - so immediately changed back to IDE/legacy.

As to the BIOS corrupting the hdd, would it not do so now and to the single hdd, then the 2nd hdd & again now with the problem 3rd hdd ?

The problem hdd is/was NEVER a boot disk - just data.

So tell me how do I change the hdd partition from 'EFI System' to 'basic data' it is and always has been a GPT hdd.

Ran chkdsk again - no problems found as well.
My System SpecsSystem Spec


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