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I'm using Windows Vsta Home Premium 32 Bit.

I Have 4 parition :


D=8GB (recovery partition)



Now i'd like to reduce the first partition about 30GB, which is 50% free. But when i click on reduce trought disk manager, i see that i can reduce only 14gb. Why this? And how can I fix this trouble without damage the partition table?

P.S. This happened, i think, because recently i added/removed a Ubuntu distro. Maybe there is some trouble?

Hope in a help! Cheers

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up vote 1 down vote accepted

It could simply be that all the data is spread out over your C: partition, and nothing more sinister than that. So long as you actually have all the space free on the drive I wouldn't have thought that the Ubuntu installation would cause a problem.

One thing I have done to help with this has been to use a program like MyDefrag to move the data on the drive.

I believe that MyDefrag has an option to consolidate data on a drive and thus move it towards the beginning of a drive. I had a drive that was 1TB in size and needed to shrink it down to about 200GB, before using MyDefrag I was in a similar position to you, afterwards I got it down to what I was expecting.

Here's an image, try the "Consolidate free space" option. You will need administrator rights in order to run MyDefrag.

alt text


Another option might be to run the Disk Cleanup Wizard to delete any temporary or unneeded files, in Vista it can also clear the System Restore files which may be free up some of the "locked" space at the cost of not being able to roll back to a previous system state, and I believe it can also delete the hibernation file which may free up some space. See the page I linked for some details of what it can do to help.

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Tried. First Optimize Daily, than Consolidate free space and, after a restart, i can reduce the same GB, as before. Nothing more... :( – markzzz Jan 20 '11 at 13:27
There is no chance to reallocate unmovable files? (Like do this scan on provvisory modality) ? – markzzz Jan 20 '11 at 13:42
Safe mode may work as well, some extra files may be movable but I wouldn't hold my breath to be honest. See my edit for another option. – Mokubai Jan 20 '11 at 18:39
Tried. But nothing change... arghh – markzzz Jan 20 '11 at 20:11
It sounds then like some important system file has locked the space you want and outside of using GParted (which carries a risk of corrupting your drive) you'll probably have to live with it. You might have some luck with upgrading or reinstalling the latest service pack as it might reinstall whatever is locking the space, but then it might just make the problem worse. Sorry I can't really help more, hopefully someone else might have a better/guaranteed to work answer. – Mokubai Jan 20 '11 at 21:14

Some Windows files are unmovable, and are unhelpfully allocated by Windows at the end or middle of the disk, so that one can only shrink C up to a limit. The disk cannot then be further reduced without destroying Windows.

You can use a defragemeter to move some of the files allocated at the end toward the beginning of the partition by choosing an option such as "consolidate free space" and trying a boot-time defrag, but some Windows files remain stubbornly unmovable.

For example, in this analyze of a disk C by Smart Defrag, the black rectangles denote unmovable system files:


The only other solution is to reinstall Windows in a smaller partition. You will need to delete the existing system partition and divide it into two partitions via a 3rd-party tool, then install Windows.

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Hi. thanks for the reply. Tried with this software. The actual scan is this one . As you can see, the black brick is far away than only 15 GB! But i still reduce the size only for 15GB. Is not so strange? :) – markzzz Jan 20 '11 at 21:02
I see several black squares about 10% from the end of the disk, so 15 GB seems to be correct. Can Smart Defrag tell which are these files? Some of them can be turned off temporarily in Windows, like the pagefile. – harrymc Jan 21 '11 at 6:35
@markzzz There's a tool from Sysinternals called DiskView that shows you a layout similar to what you have in SmartDefrag, but you can literally zoom into areas of the disk and click on the individual clusters to find out what file is there. You can get it from I can't believe I didn't think of that... – Mokubai Jan 21 '11 at 10:08
I can show these on MyDefrag too. The topper files are called $Extend\$UsnJml:$J:$DATA . I tried fsutil usn deletejournal /n c: but i get the "ERROR - Access Denied` from the console (and i am admin). I think i could move or delete them in other way? Don't know how to do this process :) – markzzz Jan 21 '11 at 18:01
@markzzz: Even if you are admin, if UAC is on then you must start cmd with "Run as Administrator". – harrymc Jan 21 '11 at 18:49

As others have described why you have the problem - there are files on the disk that Windows cannot move while it is running and so you it cannot make the partition smaller from Disk Manager - I won't elaborate further, but instead suggestion another way to get around this restriction:

The solution is to repartition while Windows is not running.
Specifically, I recommend you boot to a live OS and repartion from there.

In the past I have personally used a GParted Live CD (which is free) to shrink and move an entire Vista partion to the end of a drive to make space for another OS partition. Specifically, the Vista partition started as covering the entire 0-500GB of a drive, and ended up covering only the last 200GB. Most of the files in the partition had to be moved by GParted (this did, admittedly, take a very long time...).

GParted themselves recommend a heavy backup before this type of operation as it carries a very small risk of causing corruption.

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Tried. But it say that i cannot move some partition, or boot will be fail. Nothing to do : i'll do a total backup, a clear format and i'll reinstall all! thanks anyway – markzzz Jan 23 '11 at 12:58

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