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A second hard drive can help alleviate a lot of problems when it comes to space. I'll cover a few simple changes to put that second hard drive to use.

I have a laptop with 32 GB in drive C and 32 GB in drive D. My drive C is full and I do not know how to start using drive D.

A full C: and an empty D: is an opportunity. There are several approaches to take to start taking advantage of that second hard drive.

From system configuration settings to where you place your data we'll look at several options to make use of that second drive.

A couple might even make your computer slightly faster.

Move the Paging File

The paging file, also known as the Windows swap file, is a large hidden file that typically resides in the root of your C: drive. It's where Windows stores things when the programs you're actually running can't get enough RAM.

Moving that file to your D: drive is not only possible, but might actually make your system slightly faster, moving the swap file operations - which depending on your system configuration and usage can be heavy - to the second disk.

"My recommendation is to conceptually begin to think of 'D:' as your 'data' drive."

What is pagefile.sys and can I move it? shows how to move the paging file to another drive.

Be sure to erase the old paging file to free up its room after it's no longer in use.

Move My Documents

By default Windows stores a lot of stuff in your "My Documents" folder. In addition, many applications like the assorted Microsoft Office programs, all default to storing the documents you create there as well. On top of that most browsers will also place the files you download into My Documents as well.

As you can imagine, moving it can move a lot from C: to D: with this added benefit that D: continues to be used thereafter for all those things.

How do I change the location of the My Documents folder? shows how to move My Documents from one drive to another.

Move The Temporary Files Folder(s)

Depending on how you use your computer, and more importantly how the programs you run use your computer, moving the temporary files to another drive can often clear up some space, as well as increase performance just a bit.

To do this, create a folder on drive D: - let's call it TEMP and put it in the root of D: "D:\TEMP".

Now, for XP (others are similar), right click on My Computer, click on Properties, click on the Advanced tab (or link), and then click on the Environment Variables button. You should see something similar to this:

Environment Variables in Windows

If there are TMP or TEMP environment variables in the upper box, remove them; click on each and click Delete.

In the second box, scroll down until you find the TMP and TEMP environment variables. Click Edit..., and change the value of each to be D:\TEMP.

You may need to reboot to make this effective. After that you can visit the old temporary file location(s) and delete the contents - it's all been moved to D:.

Program by Program

We've moved some easy to move items that affect either the system as a whole, or all programs that run on the system. To make further changes, we have to deal with each application you might be using individually, or just decide to do some things differently from here on out.

My recommendation is to conceptually begin to think of "D:" as your "data" drive. That means when working in various applications when you save your work save it to a folder on D:. If you already have a collection of work, create a folder on D: and move it all there. When you download something, download it to D:.

Speaking of collections and downloads, if you have large quantities of downloaded materials like music, pictures or such, consider also moving it to a new folder you create on D:.

Typically a few "low hanging fruit" candidates can be quickly identified by tools like TreeSize outlined in Where's my disk space going?. Run the utility on your C: drive, and see of there are things taking up space that could be moved to D:.

Article C4615 - November 20, 2010 « »

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
November 21, 2010 6:04 AM

These 2 drives are most likely both on the same physical drive. If this is true would moving the swapfile make any speed difference? I've found that when disk space gets tight on a partitioned disk,the most efficient configuration would be to combine the c and d drives into the c drive using the Easus partition manager I'd also try ccleaner to clean up the temporary files and the recycle bin.

My assumption is that they were two different drives (not sure that one is more likely than the other). You're correct, if they're on the same physical drive then there's no performance gain to be had by moving things - only better space usage.

November 22, 2010 1:37 AM

When I purchased my recent desktop, it contained a single HD partitioned into two drive letters. I didn't realize at the time, but the provided Acer 'backup' software assumes it will take an image of C, and save it to D...
I've since installed a second HD (as drive E) - but the only options I find are 'make a user backup' and pick the destination. I'm still worried all it will take an image of is C, not D.

November 22, 2010 7:24 AM

Since in most cases, the d drive is used for data and not the OS, if the back up doesn't copy an image of it, you can simply copy the d drive files to the backup drive.

November 22, 2010 3:22 PM

As Bob said, Acer as their standard operating proceedure (well, as of a year ago, when they took their operation overseas) made a C: and D: partition on thier hard-drive. I worked in thier call center here in Oklahoma and we constantly had questions on that. As far as I know they still do it, but I don't hear from acer owners at my current job untill the acer warranty is over (which is 1 year from when they bought it)

November 23, 2010 12:38 AM

I ask the question about Acer's backups because I've installed software to C: and D: over time, and now I have somewhere large enough to back up to, I want to make sure...

November 23, 2010 11:02 AM

The beauty of Leo's advice is that by using C: only for the operating system and program files, C: can be relatively small which also means a fairly small backup image of C:. My XP with plenty of software takes up less than 7 GB. When C: gets corrupted (it happens), it's quick & easy to restore from image and never lose the data. Everything on D: (system backup images and all data) gets automatically synchronized with a 2nd hard disk every night giving redundant backups in case one of the disks fails.

Follow Leo's advice. Everyone should be making a backup image of C: and update it periodically.

November 23, 2010 11:48 AM

Withstanding previous comments, It should be noted that 'backup of any data, be it the operating system or data, to the 'D' drive, if it is actually a partition of a single drive of which the 'C' drive is a part of, is actually tenuous. It backs up against corruption of the original files to a degree, but not against hardware failure. Real back up is to a different spindle, most likely an external drive or second 'internal' spindle. In the case of the 'two drives' actually being a single spindle, I'd back up any data on the 'd' drive, delete the partition, expand the 'c' partition to fill the whole spindle, and do regular clones of the whole shooting match to an external drive. One caveat is if the 'd' drive is not being used as a backup, but rather a restore drive for windows (not data), in which case I would expect it to be much less in size than 'C'. This was not inferred in the original question. Software mentioned in previous comments will do all this.

Tom DAvis
November 23, 2010 2:43 PM

Are you aware that there are formatting issues associated with the display of your articles and have been for the last couple of weeks? I do not know if it is an IE issue or if possibly you have changed something in the coding of the articles. I am running XP Pro w/SP3 and IE 7.0.5730.13. If possible I would send a screen shot to show you what I mean.
Tom Davis

Frag L. Rock
November 24, 2010 11:01 AM

@ Tom Davis...use Firefox instead of buggy IE (all versions). Renders webpages beautifully and is a lot less problematic. You can even get a free IE Tab add-on for when you feel nostalgic.

Richard in Dallas
November 24, 2010 5:35 PM

A few tips gained from experience:
1. If re-installing the OS remove the D drive first. Otherwise the new OS may overwrite the D drive.
2. Make the D drive FAT32. That way you can take the D drive out and use it as a slave on any Microsoft OS. 98SE can only read FAT files.

Raisa Barkley
November 26, 2010 12:15 PM

Richard in Dallas recommended that the D drive should be formatted as a FAT32 device. My question is: If I move "My Documents" folder to the D drive will it work in this format, or must it be kept in an NTFS file structure?

Files and folders don't care what the format is. You may lose security settings - meaning that files that were protected from other users in NTFS will be accessible to all in FAT32. Other than that should work fine.

Bob Engleman
August 10, 2012 2:34 PM

When I contracted to have my current computer built, I requested a second internal drive. My problem is in accessing that area. I've scoured the Internet, but I must be incorrectly asking the question. Can I switch from "C" to "D" while XP is functioning? Must I re-start? If a re-start is necessary, how do I access the page to permit a switch?

The reason I desired a second drive was in the event of a virus problem, I wouldn't be without connectivity for business. I also have an external drive where I store all non-daily use data.

Thanks in advance for any assistance.

It's unclear what you're trying to do. In most cases a separate internal drive simply appears as D: and you can store data and whatever else you like on it.

August 10, 2012 2:57 PM

You may need to go back and consult with the folks who built the computer. What's not clear in your question is what this second drive is actually configured for. Usually a second drive is easily available right in Window's Explorer. It shows as D:, you simply click on it, and there you are.

But your question suggests that this second drive might be configured as a second boot drive, in case the first one fails. So it is quite possible that your question could only be answered by either the guys who configured it, or a hands-on tech sitting there at your computer and figuring it out!

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