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Windows 7: Drive letter disappear after reboot

08 Apr 2012   #21
dsperber

Windows 7 Pro x64 (1), Win7 Pro X64 (2)
 
 

Quote   Quote: Originally Posted by owen0729 View Post
i don't get what he meant by wrote the zero in the first and the last bits of the drive. what does it mean and how would i do it?
I have no idea. Very flimsy description of what he did, if you ask me.

And besides, there's an awful lot of important stuff going on in those "first bits" of the drive. It's obviously impossible for him to have conceivably have known what was really going on.

Plus, although I haven't installed or run this WD diagnostics utility it clearly warns that YOU WILL LOSE YOUR FILE SYSTEM AND DATA. It doesn't say you might... it says YOU WILL. How much stronger of a warning can you read that implies this to be a complete low-level format of the entire drive. I can't imagine there is any selectivity.

Yes, there seems to be an option for (a) Quick Erase, and (b) Full Erase, but without reading the README or instructions/documentation I don't know how the program works. But it's only reasonable to believe that this is a complete low-level FORMAT of the entire drive, and you'd lose EVERYTHING on the drive. Assume that is true. Now, if you want to preserve some data that's currently on the drive you'll need to back it up somehow first, so that you can restore it after the low-level FORMAT zeroes out the entire drive. If you have no backup/restore capability that can guarantee you won't lose any data on this drive, then don't consider any of this as remotely possible. It's just not possible... if you have irreplaceable data on this drive and cannot backup/restore it.

So, again... his comments are "wacky" to me, and I'm sure there's more to the explanation for why his drive suddenly began holding on to the drive letter across boots. But it IS your exact problem, so it's worth at least thinking about what makes his story similar to or different from yours.

You haven't explained where this second WD drive came from. Was it brand new as part of all the new equipment you bought when you built your new PC? Was it a replacement for an older drive? How did it get formatted for use in your new PC from out-of-the-carton? Did you just assume it was usable, or did you initialize it in some way?


My System SpecsSystem Spec
.
09 Apr 2012   #22
owen0729

Windows 7
 
 

Quote   Quote: Originally Posted by dsperber View Post
Quote   Quote: Originally Posted by owen0729 View Post
i don't get what he meant by wrote the zero in the first and the last bits of the drive. what does it mean and how would i do it?
I have no idea. Very flimsy description of what he did, if you ask me.

And besides, there's an awful lot of important stuff going on in those "first bits" of the drive. It's obviously impossible for him to have conceivably have known what was really going on.

Plus, although I haven't installed or run this WD diagnostics utility it clearly warns that YOU WILL LOSE YOUR FILE SYSTEM AND DATA. It doesn't say you might... it says YOU WILL. How much stronger of a warning can you read that implies this to be a complete low-level format of the entire drive. I can't imagine there is any selectivity.

Yes, there seems to be an option for (a) Quick Erase, and (b) Full Erase, but without reading the README or instructions/documentation I don't know how the program works. But it's only reasonable to believe that this is a complete low-level FORMAT of the entire drive, and you'd lose EVERYTHING on the drive. Assume that is true. Now, if you want to preserve some data that's currently on the drive you'll need to back it up somehow first, so that you can restore it after the low-level FORMAT zeroes out the entire drive. If you have no backup/restore capability that can guarantee you won't lose any data on this drive, then don't consider any of this as remotely possible. It's just not possible... if you have irreplaceable data on this drive and cannot backup/restore it.

So, again... his comments are "wacky" to me, and I'm sure there's more to the explanation for why his drive suddenly began holding on to the drive letter across boots. But it IS your exact problem, so it's worth at least thinking about what makes his story similar to or different from yours.

You haven't explained where this second WD drive came from. Was it brand new as part of all the new equipment you bought when you built your new PC? Was it a replacement for an older drive? How did it get formatted for use in your new PC from out-of-the-carton? Did you just assume it was usable, or did you initialize it in some way?
i just built it last friday. nothing happen until today
My System SpecsSystem Spec
09 Apr 2012   #23
F5ing

Windows 7 Ultimate x64
 
 

From the WD doc:

"WRITE ZEROS:
This option can be used to erase operating systems and file systems. The QUICK ERASE writes zeros to the
first and last million of sectors and the FULL ERASE writes zeros to the entire drive and may take hours to
complete depending on the drive size and system performance. "

I guess what happens is that since the MBR/PBR is written over with zeroes, the OS let the poster in the other thread start over from scratch with that drive.

Either way, if you do either method with that WD utility, agree 100% with dsperber. Get your data off of there first. FULL ERASE: all is gone. QUICK ERASE: only the stuff between the extremes is recoverable, but only with special software.
My System SpecsSystem Spec
.

09 Apr 2012   #24
dsperber

Windows 7 Pro x64 (1), Win7 Pro X64 (2)
 
 

Quote   Quote: Originally Posted by owen0729 View Post
I just built it last friday. nothing happen until today
You mean this "vanishing E" symptom has been with you from the moment you finished the cold install of Win7? Amazing.

If you have a usable "system image" backup (so that you wouldn't lose any time really, if you had to restore it) why not just start all over again, and reinstall Win7 one more time from scratch?

Is there anything on that WD drive you need to save? If no, then you have all kinds of options available as far as cleaning everything on it (as the other poster in that other thread apparently did). In other words maybe there's something flaky in the MBR or partition table or who knows what. Certainly zeroing out the drive and re-creating the E partition on it from zero can only help things, in my opinion.

But if you do have "real data" on that drive, copy it somewhere else first (do you have an external USB drive?) so that you won't lose it. Then wipe the drive and see what happens.

Don't know what else to suggest? Your story and the other thread story appear to be pretty much identical, and his problem was resolved by zapping the drive and formatting it and recreating his own E partition, thus probably repairing some problem with the partition table on the drive I'm guessing, but who knows.
My System SpecsSystem Spec
10 Apr 2012   #25
owen0729

Windows 7
 
 

Quote   Quote: Originally Posted by sibbil View Post
From the WD doc:

"WRITE ZEROS:
This option can be used to erase operating systems and file systems. The QUICK ERASE writes zeros to the
first and last million of sectors and the FULL ERASE writes zeros to the entire drive and may take hours to
complete depending on the drive size and system performance. "

I guess what happens is that since the MBR/PBR is written over with zeroes, the OS let the poster in the other thread start over from scratch with that drive.

Either way, if you do either method with that WD utility, agree 100% with dsperber. Get your data off of there first. FULL ERASE: all is gone. QUICK ERASE: only the stuff between the extremes is recoverable, but only with special software.
thank you for explaining it. i tried the write zeros it worked.
My System SpecsSystem Spec
10 Apr 2012   #26
owen0729

Windows 7
 
 

Quote   Quote: Originally Posted by dsperber View Post
Quote   Quote: Originally Posted by owen0729 View Post
I just built it last friday. nothing happen until today
You mean this "vanishing E" symptom has been with you from the moment you finished the cold install of Win7? Amazing.

If you have a usable "system image" backup (so that you wouldn't lose any time really, if you had to restore it) why not just start all over again, and reinstall Win7 one more time from scratch?

Is there anything on that WD drive you need to save? If no, then you have all kinds of options available as far as cleaning everything on it (as the other poster in that other thread apparently did). In other words maybe there's something flaky in the MBR or partition table or who knows what. Certainly zeroing out the drive and re-creating the E partition on it from zero can only help things, in my opinion.

But if you do have "real data" on that drive, copy it somewhere else first (do you have an external USB drive?) so that you won't lose it. Then wipe the drive and see what happens.

Don't know what else to suggest? Your story and the other thread story appear to be pretty much identical, and his problem was resolved by zapping the drive and formatting it and recreating his own E partition, thus probably repairing some problem with the partition table on the drive I'm guessing, but who knows.
thank you so much for helping me for so long. i tried the write zero it worked.
My System SpecsSystem Spec
10 Apr 2012   #27
F5ing

Windows 7 Ultimate x64
 
 

Quote   Quote: Originally Posted by owen0729 View Post
...i tried the write zero it worked.
Good to hear the problem is corrected! Mind posting back one more time to let us know whether it need a Quick or a Full overwrite?
My System SpecsSystem Spec
11 Apr 2012   #28
owen0729

Windows 7
 
 

Quote   Quote: Originally Posted by sibbil View Post
Quote   Quote: Originally Posted by owen0729 View Post
...i tried the write zero it worked.
Good to hear the problem is corrected! Mind posting back one more time to let us know whether it need a Quick or a Full overwrite?
The quick fixed mine, but i don't know it has to be quick. maybe someone encounter this problem use quick first, if that didn't work then use the full.
My System SpecsSystem Spec
11 Apr 2012   #29
F5ing

Windows 7 Ultimate x64
 
 

Thanks for your response. That tells me all you have to do is zero out the MBR/PBR on the disk to get Windows to re-identify the disk as one that's never been connected (re-writes what it knows about the disk in the registry).

Maybe or likely, but another data point to keep in mind.

Thanks...
My System SpecsSystem Spec
11 Apr 2012   #30
dsperber

Windows 7 Pro x64 (1), Win7 Pro X64 (2)
 
 

Now wait a minute... I find this whole solution to be quite astonishing, because there is significant other information which you haven't provided to us to really close out the story.

Obviously, re-initializing (i.e. low-level format of especially the very beginning of the drive where the MBR sectors and partition table and file system root live) is tantamount to wiping the drive clean and taking it out of a brand new carton. Essentially you have a brand new drive, and you should have lost ALL of any data on that drive, as well as ALL partitions on that drive (although you only had one, according to your original screenshot).

So whatever corruption had somehow made its way onto that drive/partition, obviously FORMAT is going to clean that out. The fact that you say using the WD utility to "write zeros" in QUICK ERASE mode (to write zeros just to the beginning and end of the drive) "fixed the problem", I am guessing you mean that the newly created partition on that drive and the newly [re-]assigned drive letter (E again?) is now "sticking" across re-boot. So your problem IS solved.

But... you did lose everything previously on that drive, right? You did have to re-create a new partition on that drive, and get a new drive letter assigned for that newly recreated partition, right? Was there anything on that drive that you needed to preserve first, and copy back after the FORMAT? Or did you just toss it all away and "start from scratch", with this low-level format to "write zeros" with QUICK ERASE?


I'm certainly glad that we were able to work through this problem of yours, but the real credit goes to that poster on the other thread I happened to locate where the "solution" (of re-FORMAT of the drive, QUICK or LONG) was made public. I only shared it.

Very interesting, that "corruption" of MBR/partition table can cause this symptom, of not having assigned drive letters hold across boot. FORMAT obviously recreates MBR/partition table when you use Windows to create a brand new partition on what it believes to be a brand new and empty drive.

Fascinating.
My System SpecsSystem Spec
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