2nd HD logical drive has 7.84 mb unallocated space

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I have a second HD Set up as full logical drive. It has a 7.84mb unallocated space.
Can I partition this space as another drive without causing problems with the already allocated space?
I have found no way to add it to the full already allocated drive space. I have Easeus Partition Master Pro.

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Leave it be. I tried earlier also to absorb that into my usable partitionable formattable territory. Ended up simply continuing to work my plan of rePartitioning, reFormating my harddrive as C & D logical drives. That little bit apparently belongs to something within the harddrive. Leave it be. 🙂

Addendum: later post by dg1261 labels this as a first cylinder reserved for the partition table…see later post by dg1261.

"Take care of thy backups and thy restores shall take care of thee." Ben Franklin, revisted

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No, you cannot. 7.84MB is precisely the size of one cylinder* on a traditional MBR-type disk, so it’s evident you setup the partition layout as a single logical volume within a partition of “Extended” type on a MBR-type disk.** In such a scenario the first cylinder is reserved for the partition table so cannot be included in any logical volume.

It is very unfortunate that Easus persists in marking this as unallocated space. Yes, it is technically “unallocated” to any logical volume, but by displaying it as such it leads people to think they can allocate it for something when they cannot. Smarter partition managers would not display space to the user that the user cannot allocate.

As a practical matter, think about how little space you’re fretting over. 7.84MB is the size of about 7 floppy disks. It’s 1/90 of a typical CD disc, or about 0.001% of a regular DVD disc. Seriously, how much more utility would that space provide if you were able to use it?

Footnotes:

* 7.84MB = 255×63 sectors of 512 bytes/sector on most computers. HP/Compaq/Lenovo computers notably use 240×63 sectors per cylinder, or 7.38MB.

** Unlike a Primary partition, an Extended partition may contain multiple logical volumes. Microsoft refers to these logical volumes as “logical drives”, but they are part of a single partition of “Extended” type. Because of the way you setup the partition layout, there is a tad more wasted space because there are two partition tables–the primary table that defines the Extended partition and the secondary table that defines the logical volume within that partition. If you had setup the layout as a single Primary partition you would have wasted less space… but, again, think of the miniscule amount we’re talking about here. It is not worth repartitioning to reclaim such a small amount of space, so just leave it be.

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Thank you DG1261 for your information!
You are correct in that I have drive 0 set up with primary for C: and then 2 logical partitions as D: and E:. I have the second drive 1 set up as logical drive F: with only one Partition.
From the old school that I came from, you could not have but only one primary partition, so I set Drive 1 up as logical. Does this hold true today for only one primary partition allowed? Just curious as I will be leaving my drives as I have them now….they are working fine. I just wanted to know about the free space of 7.84mb because I thought I had done something wrong.
Thank you again!

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From the old school that I came from, you could not have but only one primary partition, so I set Drive 1 up as logical. Does this hold true today for only one primary partition allowed?

That “old school” was back in the DOS/Win9x days. It is not true any longer. In fact, it wasn’t a hard and fast rule even then–one could have multiple primaries with DOS if you chose to do so, but there was a bug in DOS that could cause data corruption in certain scenarios so it was wise to avoid multiple primaries if they weren’t absolutely necessary.

Since Win9x was based on DOS, the same advice applied to Win95, 98 and ME.

Win NT/2000 and later were not based on DOS, so did not have the bug. However, it’s interesting that when left to assign drive letters by itself, NT/2000 and all later OS’s–even Windows 8–will enumerate visible partitions per the old DOS scheme–that is, active primary first, followed by logical drives, and additional primaries last. (See my webpage here for more info.) That isn’t a bug, and isn’t even a problem because in those OS’s one can change the drive letter after the fact to anything you want. Nowadays that’s nothing more than a leftover idiosyncrasy.

Since you do not have more than four volumes on Disk0 you could have made all three primary partitions, but there’s really no advantage one way or the other. The single volume on Disk1 could have been either a primary or logical.

While the OS has no trouble handling either type of partition, beware the use of Windows Disk Management if you have occasion to hide any partitions. Hiding doesn’t include simply removing a drive letter in DiskMgmt, it means preventing access by Windows altogether–a technique that’s generally used when multibooting using linux or a third-party boot manager (such as Terabyte’s “BootIt Bare Metal“). That doesn’t mean you shouldn’t hide partitions, it means that if you do you’ll want to use a decent tool for managing your partitions and not the half-witted DiskMgmt. Again, that shouldn’t be a problem if you don’t multiboot, but I mention it here for the benefit of readers who might be multibooting.

Dan

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Thanks again dg1261! You information is worth saving.
My old days were with DOS 3.0, before Windows, with a 4k memory computer. I now am running W7 pro. I have a lifetime paid version of Easeus Partition Master.
I never knew, before your information, that you could use more than one primary without problems and nowhere I saw why the unused space.
I see where EPM can change from logical to primary. I may try this change when I get brave.
Thanks to the rest of you that replied to my questions. Windows Secrets and it’s users never lets you down! I have my question answered!

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dg1261, when I first started using Acronis Disk Director 10, later 11 & 12 — I wasn’t “told” by ADD this 7+MB was unusable by anyone. So, hopefully, future editions will do so.

"Take care of thy backups and thy restores shall take care of thee." Ben Franklin, revisted

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GUG,

With a MBR disk you can have up to 4 Primary partitions (only ONE Active).
With the new GPT disk type you can have as many as you want, however Windows only allows up to 128 (should be enough?).

HTH :cheers:

May the Forces of good computing be with you!

RG

PowerShell & VBA Rule!
Computer Specs

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With the new GPT disk type you can have as many as you want, however Windows only allows up to 128 (should be enough?).

I am curious, what does Windows do after it gets to Z??

🍻

Just because you don't know where you are going doesn't mean any road will get you there.

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David,

See Using Mounted Drives here. HTH :cheers:

May the Forces of good computing be with you!

RG

PowerShell & VBA Rule!
Computer Specs

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RG
I looked at the link but (maybe I just did not look close enough) I still don’t know what Windows does when the 27th Basic drive goes on line. Not that I envision ever having to deal w/ that situation :p

🍻

Just because you don't know where you are going doesn't mean any road will get you there.

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David,

You can “mount” partition #27 to a folder in a drive with an assigned letter. ( Instructions ).

So you could have a Drive Z and with in that drive have a folder called DriveAA. You would then mount the 27th partition to that folder. Following on you could have a folder called DRIVE AB and mount the 28th partition to that folder, etc. Yes it makes the references a little longer since they would be z:DriveAA… but it would allow you to mount unlimited (of in Windows case the other 101) partitions.

I hope this makes sense and that I’ve understood what I’ve read about this feature. Unfortunately, I’m traveling and don’t have access to a machine that I can test this on. HTH :cheers:

May the Forces of good computing be with you!

RG

PowerShell & VBA Rule!
Computer Specs

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In English its painful and annoying ‘but’ leave be and ignore it. It’s a hard drive thing and just has to be
The tech bit has all been said above, I would not suggest playing around with it thou

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Unless you use Bitlocker or you do not have a GPT formated boot drive you can indeed remove or on a clean install never create the System Reserved partition. You sure don’t recover much of a modern hard drive though.

https://technet.microsoft.com/en-us/magazine/gg441289.aspx

http://www.terabyteunlimited.com/kb/article.php?id=409

http://forum.scottmueller.com/viewtopic.php?p=16024#p16024

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