Unallocated space question?

Hi, I am completely new to ADS 10. I have just read the PDF manual.

When I opened the main window for the first time, I could see the only HD I have (it's a laptop) and a 7.88 MB unallocated space at the begining of the disk(probably created by XP as default). This unallocated space does not appear on the XP disk management console. Some info about it? Is it requested and if so, why?

Now my question:
When I tried several options to modify my 2 partitions (C: and D by increasing, moving, etc. ADS actually removed this unallocated space when I maximized the 2 partitions. Is is safe? What's troubling me is that on the External USB-HDs, this unallocated space cannot be removed but only moved at the beginning or at the end of the partition.

Print screen of the HD without unallocated space and 2 external USB-HDs with unallocated space

 

That space is perfectly normal. DD shows it. Disk Management doesn't show it (also normal). When you only have one or more Logical partitions on a drive, a small amount of space is reserved. This space is usually located at the beginning of the drive, but can also be at the end.

It shouldn't cause a problem.

This is normal. Don't worry about it.

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I notice that your E: partition is showing the "red C" on the partition. This usually means that DD has detected errors in the partition. You may want to run chkdsk /f or chkdsk /r on the partition to check it. However, if this partition is a special, non-standard partition, don't run chkdsk on it as it may cause data loss.

 

Hi MudCrab

E is a TrueCrypt volume (I should have mentioned it) that's why DD marks it with a red C.

Let me confirm: when a disk has one or more logical partitions there is an unallocated space created at its beginning. DOES that apply too when the disk has one or more PRIMARY partition only?

What is the purpose of this unallocated space, if any?

In the example above where I have removed this empty space by MOVING it at the end and ten by EXTENDING the logical partition D:\ to its maximum value, shouldn't I restore it?

AM

PS: thanks for the info BOOTWIZ.OSS File

 

That explains it. Thanks.

It can. I've seen it on drives with just one Primary partition. I think it's more of a placeholder for creating another partition (a Primary partition, for example, if you only have Logical partitions). It may also have to do with which program created the partitions. DD will do things Windows Disk Management won't, for example. In any case, the space, used or not, is nothing abnormal.

If it's work okay, I'd just leave it.

This really isn't a case of correct vs. incorrect. Either way is okay.

 

All clear now. Question answered. Help much appreciated

 

If you use a Windows tool to create the partitions there will also be a small unallocated space on the drive. Microsoft's reason for this is to reserve space in case you ever want to convert any of your disks to dynamic disks. A dynamic disk requires at least 1 MB of unallocated space on the drive or the conversion will not succeed.

I don't know where the 7.88 MB number comes from...

 

Thanks for this new information k0lo

 

Doh! I wasn't thinking clearly last evening. 7.88 MiB is the size of one cylinder on the disk, or the minimum size for a partition that is aligned on cylinder boundaries.

 

That makes sens now. Thank you to complete this information.