Harddisk Capacity in Explorer and Computer Management

[Beyond X]

My 1.5 TB harddisk (Seagate SATA) in a XP computer has been set up with
two partitions: one 81 GB for system and programs and the other 1300 GB
for data storage, as indicated in Disk Management in Computer Management
of Admin Tools.
However, Windows Explorer shows C: 81GB, which is OK, and D: 849 GB,
which is inconsistent with the value shown in Disk Management and now
almost full. Where is the remaining 450 GB? How can I use the full 1300
GB? Is it possible to expand the usable space without losing the already
stored data?
Help will be highly appreciated.

 

[Ken Blake, MVP]

My 1.5 TB harddisk (Seagate SATA) in a XP computer has been set up with
two partitions: one 81 GB for system and programs and the other 1300 GB
for data storage, as indicated in Disk Management in Computer Management
of Admin Tools.
However, Windows Explorer shows C: 81GB, which is OK, and D: 849 GB,
which is inconsistent with the value shown in Disk Management and now
almost full. Where is the remaining 450 GB? How can I use the full 1300
GB? Is it possible to expand the usable space without losing the already
stored data?

It isn't clear exactly where you are seeing the 849GB number. Is that
the total size of the files written on the partition? If so, be sure
you are adding up "Size on disk, not "Size." Disk space is allocated
in units called clusters. The default NTFS cluster size is 4K (4096
bytes), so, for example, if you have a file that's 16,385 bytes (one
byte more than 4 clusters), its size on disk is 5 clusters, or 20,480
bytes. The rest of that last cluster is unused, and is called slack
space.

On the average, each file has about half a cluster of unused, slack
space, so Size on disk is always larger than Size.

 

[Beyond X]

As you know, when you highlight a partition, Explorer's properties show
three numbers, i.e., Used space, Free space and Capacity. In this case
they are 70.8 GB, 10.7 GB and 81.5 GB, respectively, for C:, and 806 GB,
43.7 GB and '849' GB, respectively, for D:.
Values of "Capacity" as the sum of "Used space" and "Free space" should
be equal to the capacity of the entire disk as Disk Management is showing.
So, Window's Explorer evidently is not seeing the entire partition (D.
But where does it get the spurious number of 849 GB? This is the question.
Incidentaly, my partition manager software (Paragon) also shows the size
of D: being equal to 1315.6 GB, which is same as the value seen in Disk
Management.
Beyond X

 

[Paul]

As you know, when you highlight a partition, Explorer's properties show
three numbers, i.e., Used space, Free space and Capacity. In this case
they are 70.8 GB, 10.7 GB and 81.5 GB, respectively, for C:, and 806 GB,
43.7 GB and '849' GB, respectively, for D:.
Values of "Capacity" as the sum of "Used space" and "Free space" should
be equal to the capacity of the entire disk as Disk Management is showing.
So, Window's Explorer evidently is not seeing the entire partition (D.
But where does it get the spurious number of 849 GB? This is the question.
Incidentaly, my partition manager software (Paragon) also shows the size
of D: being equal to 1315.6 GB, which is same as the value seen in Disk
Management.
Beyond X

If the partitions are all Primary ones and not extended (logical),
you can use this utility to capture the partition table (size info).
This is physical space, the number of sectors.

The screenshot of the program is here.

http://www.vistax64.com/attachments...n-partiton-recovery-dell-xps-420-dell-tbl.gif

The download is here. Unzip and execute. If Paragon shows 1315.6,
after some math, this probably does as well.

ftp://ftp.symantec.com/public/english_us_canada/tools/pq/utilities/PTEDIT32.zip

What happens if you use chkdsk ? I just ran it on a small NTFS partition
here. as in

chkdsk V:

I don't think that is correcting anything. But it does print out some statistics
when the check is finished.

46082452 KB total disk space.
32154556 KB in 636 files.
344 KB in 59 indexes.
0 KB in bad sectors.
68120 KB in use by the system. \___ double counting...
65536 KB occupied by the log file. /
13859432 KB available on disk.

4096 bytes in each allocation unit.
11520613 total allocation units on disk.
3464858 allocation units available on disk.

ptedit32 says the partition has 92164905 sectors. Times 512 bytes divided
by 1024 gives 46082452.5 KB. Of the above numbers, the "in use by the system"
is counting the same space as the "occupied by the log file". When I
remove the log file number, the rest of the entries balance.

32154556+344+0+68120+13859432= 46082452

Try running chkdsk without correcting anything, and see what stats it
reports. See if the numbers balance, there are a large number of
bad sectors, or something...

Paul

 

[Beyond X]

I sent a response to you but it seems it did not go through, so I am
writing again.
First thanks a lot for your thought and time.
1. I downloaded the software you suggested. I will attach the result as
shown below. Please tell me what information you can extract from there.
2. I tried to get information from CHKDSK w/o switches, but the message
window closes after momentarily showing that verifying files, indexing
and security(?) are completed. I do not know where I can see the data.
(I tried Eventviewer, but it doesn't show anything.)
3. Paragon has the feature which allows expansion of a partition into
unused space. I am just afraid that if I go ahead, it might screw up the
whole partition and the stored data.
Starting Ending Before
type boot cyl head sect cyl head sect sect sector
1 07 80 0 1 1 1023 254 63 63 171060057
2 07 00 1023 0 1 1023 254 63 171060120 2759211945
3 00 00 0 0 0 0 0 0 0 0
4 00 00 0 0 0 0 0 0 0 0

 

[Paul]

I sent a response to you but it seems it did not go through, so I am
writing again.
First thanks a lot for your thought and time.
1. I downloaded the software you suggested. I will attach the result as
shown below. Please tell me what information you can extract from there.
2. I tried to get information from CHKDSK w/o switches, but the message
window closes after momentarily showing that verifying files, indexing
and security(?) are completed. I do not know where I can see the data.
(I tried Eventviewer, but it doesn't show anything.)
3. Paragon has the feature which allows expansion of a partition into
unused space. I am just afraid that if I go ahead, it might screw up the
whole partition and the stored data.
Starting Ending Before
type boot cyl head sect cyl head sect sect sector
1 07 80 0 1 1 1023 254 63 63 171060057
2 07 00 1023 0 1 1023 254 63 171060120 2759211945
3 00 00 0 0 0 0 0 0 0 0
4 00 00 0 0 0 0 0 0 0 0

Go to Start : Programs : Accessories : Command Prompt.

A black window will open. It looks like MSDOS, but is an emulation of it.

Type the command in there, like my example.

chkdsk V:

The Command Prompt window will stay open, until you choose to
close it.

You can even copy text from the Command Prompt window, but it
doesn't seem to be a very easy to explain procedure. In the
various environments I use here, no two Command Prompt windows
seem to behave exactly the same :-(

Paragon is showing two (07) NTFS partitions. The first one is 171060057
sectors or 87,582,749,184 bytes.

The second one is 2759211945 sectors or 1412,716,515,840 bytes.
If I divide that by 1024*1024*1024, I get 1315.694 , which is
what you were claiming in your original post. So that is space
now allocated for that partition, for whatever is actually
stored in there.

Now, I await a copy/paste of your chkdsk

Paul

 

[Beyond X]

OK. I got the following:
(In my previous response I once attached the screenshot as an attached
file. If it a regular e-mail, the picture would appear at the end of the
text. In the NG communication, however, the whole thing does not go
through. You use a web link, but I do not have that luxury. So bear my
typing.)

chkdsk D:
----
---- completed.
Window has checked the file system and found no problem.

891229942 KB total disk space -> 891 GB
738297852 KB in 6690 files -> 738 KB
3116 KB in 895 indexes
0 KB in bad sector
103352 KB use by the system
65536 KB occupied by the log file
152825620 KB available on disk -> 152 GB

4096 bytes in each allocation units
222807485 total allocation units on disk
38206405 allocation units available on disk

It appears that CHKDSK concerned only the area (891 GB) that is viewed
by Explorer/Properties (849 GB). (Similarly CHKDSK found 738 and 152 KBs
for used and available, respectively, total being 891 KB.)
So here confirmed is the discrepancy between the capacity detected by
Explorer/CHKDSK and the capacity tallied by Disk Management. The
question remains :what is half-blinding Explorer/CHKDSK?

 

[Paul]

OK. I got the following:
(In my previous response I once attached the screenshot as an attached
file. If it a regular e-mail, the picture would appear at the end of the
text. In the NG communication, however, the whole thing does not go
through. You use a web link, but I do not have that luxury. So bear my
typing.)

chkdsk D:
----
---- completed.
Window has checked the file system and found no problem.

891229942 KB total disk space -> 891 GB
738297852 KB in 6690 files -> 738 KB
3116 KB in 895 indexes
0 KB in bad sector
103352 KB use by the system
65536 KB occupied by the log file
152825620 KB available on disk -> 152 GB

4096 bytes in each allocation units
222807485 total allocation units on disk
38206405 allocation units available on disk

It appears that CHKDSK concerned only the area (891 GB) that is viewed
by Explorer/Properties (849 GB). (Similarly CHKDSK found 738 and 152 KBs
for used and available, respectively, total being 891 KB.)
So here confirmed is the discrepancy between the capacity detected by
Explorer/CHKDSK and the capacity tallied by Disk Management. The
question remains :what is half-blinding Explorer/CHKDSK?

Give Sysinternals NTFSInfo a try. I just found this in a search.
The only thing this adds, is the ability to get info about
the MFT. This runs in a Command Prompt (MSDOS) window.

http://technet.microsoft.com/en-us/sysinternals/bb897424.aspx

This compares my chkdsk info, against the ntfsinfo output.

******* chkdsk output *******
46082452 KB total disk space.
32154556 KB in 636 files.
344 KB in 59 indexes.
0 KB in bad sectors.
68120 KB in use by the system. \___ double counting...
65536 KB occupied by the log file. /
13859432 KB available on disk.

4096 bytes in each allocation unit.
11520613 total allocation units on disk.
3464858 allocation units available on disk.
*****************************

******* NTFSInfo *******
NTFS Information Dump V1.01
Copyright (C) 1997 Mark Russinovich
http://www.sysinternals.com

Volume Size
-----------
Volume size : 45002 MB <--- 46082452/1024 = 45002
Total sectors : 92164904
Total clusters : 11520613
Free clusters : 3370532
Free space : 13166 MB (29% of drive)

Allocation Size
----------------
Bytes per sector : 512
Bytes per cluster : 4096
Bytes per MFT record : 1024
Clusters per MFT record: 0

MFT Information
---------------
MFT size : 0 MB (0% of drive)
MFT start cluster : 786432
MFT zone clusters : 786592 - 836448
MFT zone size : 194 MB (0% of drive)
MFT mirror start : 6399894

Meta-Data files
---------------
************************

If I run this command in the Command Prompt, I get the same info

fsutil fsinfo ntfsinfo V:

I doubt your lost space is all MFT. That is why
I'm hoping someone else will hop in and comment, because
I can't see this just being a math error or an accident.

http://www.mydefrag.com/forum/index.php?topic=1323.0

I've never used quotas, and don't even know how size
info would be listed if a quota is in place. Check
the properties on that partition.

http://arstechnica.com/paedia/n/ntfs/quota-1.gif

Paul