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Many, but not all programs allow you to specify their install location. In some, however, that ability is somewhat hidden in the install process.

How can I install applications to the D: drive in Windows Vista? The C: drive is full and every program wants to load itself into it. I tried saving the application on the D: drive and running it from there, hoping I would get a prompt saying "setup will install this program in C:\Program Files..... if you want to install it elsewhere browse for the location" but the application just automatically installs itself in the C: drive without giving me another option. It then gives an error message saying not enough disc space in C:. How can I do this?

You may not be able to.

But then again, depending on the application, you may.

And that phrase is kind of what it boils down to: "depending on the application".

In your situation, I'd make sure to first have cleaned up that C: drive as much as you can. Even though we may install applications onto other drives, there's still no getting around the fact that Windows, and programs running under Windows, will need some amount of space on C:.

"If it doesn't ask, then there's almost nothing you can do."

I'd point you toWhere's my disk space going? as a place to start. It includes references to a couple of tools that may help you identify exactly what's eating up all the space on your C: drive. Knowing that you may be able to make some decisions on what steps to take to free some of it up.

Where you download your install program actually makes no difference at all to where that program may try to install itself. The key is that at some point in the installation process it must ask you where you want it to install. If it doesn't ask, then there's almost nothing you can do. It'll install where it installs, and that's likely going to be C:.

Many programs are nice enough to just ask:

PDF Creator asking where to isntall

That's PDFCreator asking where you want it to be installed. No special steps were required, it simply includes this as part of the normal setup process. If you want to install it to a different drive you can simply enter the new location here.

Another common scenario has that setting available, but hidden.

Here's a step in the Open Office installation process:

Setup Type request in Open Office install

As I said, this particular scenario is very common as setup designers want to make it easy for people to simply take the default settings that might otherwise confuse or concern them.

Hint: don't. Smile

In this case, choose Custom, and the next step looks something like this:

Open Office Custom Setup highlighting the Install To information

As you can see, the setup program now displays where it will install the software, as well as a Change... button so you can alter that. Click that and:

Open Office Setup install location selector

You can select exactly where the installation should happen.

The specifics of this scenario will vary from application to application, but the big take-away is to choose the "advanced" or "custom" installation option if it's offered. Nine times out of ten, the install location is hidden therein.

Unfortunately, if it's not, and there's no other place to specify it as part of the install, then there's little you can do.

Article C3799 - July 1, 2009 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

Mark Jacobs
July 1, 2009 1:30 PM

It's sometimes risky to install a program on a drive other than c: because plugging in a device or something you may inadvertanty do may change the drive letters on your computer. Why not move a lot of your data files instead?

July 2, 2009 7:46 AM

@Mark Jacobs:
Fixed disks (mounted inside the case) don't change drive letters between boots.

It is never a good idea to install software on a Windows machine on a removeable drive.

Ken B
July 2, 2009 9:59 AM

It used to be that adding a second drive with a primary partition on it would cause the secondary partition(s) on the primary drive to shift. (ie: the primary partition on the second drive became D:, and the former D: became E:.) I haven't seen that behavior in Windows for many years. I don't believe I have ever seen that happen when installing a removable device.

July 7, 2009 10:53 AM

I would recommend to make room on the C: partition by moving the user files (Documents, Pictures, Videos, etc.) to D:. That is dead easy and will free up room.

Mr J McGarry
July 7, 2009 10:56 AM

for what it is worth I have installed windows from Win95a Win95b Win95c Win98se to my current Win XP in the last few times I find it it a good idea to make three hard drives. the first one is half of the whole. The second is half of the remainder. That way I have enough space to cover everything that I want on the drive.

July 8, 2009 2:10 AM

It is possible to force-assign a drive letter using Disk Management. Of course, if you have lots of drives, it is necessary to mess around removing/changing lots of drive letters.

Torben Reffeld
July 8, 2009 3:00 AM

In the registry in the key
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion] there is a sting called ProgramFilesDir, by default with the value C:\ProgramFiles. If the value is changed to D:\ProgramFiles, I feel sure Windows wil propose this directory for installeng new programs. I have not tried this, and there might be a risk to confuse Windows with respect to allready installed programs, but why should there?

July 11, 2009 9:00 PM

If there is an option to install to other thban Drive C, I always install programs on another drive. For one thing, even if you have to reformat C Drive, at least some programs, usually utilities, will still work. In addtion it helps to remember which programs you were using, as you will still be able to see them. You may not want to reinstall all of them, but it will be easier to remember which ones ou want to continue using. And of course even Windows does not ahve to be installed on C drive. I've installed it on many other drives leaving C to contain the bootup information. At any rate I have never had a problem caused by installing programs on other drives.

July 23, 2009 9:12 AM

Is it better to install programs on a separate drive, such as a partitioned D, and not on the C drive where my Windows XP is installed? I've been told this is better for the Windows system and less prone to slowing down but it can be so bothersome to have to make sure I'm not installing on the C every time.

While there might be a slight difference, I don't think it's significant. There's an argument for putting your data on a different drive, though, for ease of backup and restore.
- Leo

January 3, 2010 11:06 AM

"""""""""""Posted by: JH at July 8, 2009 2:10 AM
In the registry in the key
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion] there is a sting called ProgramFilesDir, by default with the value C:\ProgramFiles. If the value is changed to D:\ProgramFiles, I feel sure Windows wil propose this directory for installeng new programs. I have not tried this, and there might be a risk to confuse Windows with respect to allready installed programs, but why should there?"""""""""""""

I have tried this on my computer and this is possible, you just need change the path from C: to D: and restart computer and then all your program by default go to d: drive or a particular folder in it

January 27, 2010 1:16 PM

I have also heard that installing the os to the c: drive and programs to another drive is a good idea, particularly on a server. In fact, I believe that Dell offers this as an option when you order a server from them. I agree that it's a good idea to keep data on a separate drive, but most of my saved data exists in the "My Docs" folder. Can you move the location of "My Docs" to another drive, or will this confuse Windows?

February 14, 2010 8:54 AM

Thank you so very much for the registry tip. I absolutely hate when a program doesn't give you the choice. I shouldn't have to delete programs on C drive when I have 200 gigs to use on D!!!!

August 12, 2010 1:51 PM

If the C-drive and the D-drive are on different physical drives, there likely would be some gain in speed. If D is merely a partition, there would be little, if any gain.

BTW, if you have separate drives, moving the switch file (virtual memory) to the D drive can provide significant gains.

Bevin Meadows
March 20, 2012 11:38 AM

Oh, the irony! I arrived here when trying to figure out how to install the first example (PDF Creator) to a drive other than C:. Alas, they no longer give an installation prompt.

April 16, 2013 8:37 AM

can u please tell me how to install updates on other drives my c drive is almost full and no space is occoupied on d and e

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