03:39 PM
Fred Langa
Fred Langa

The Explorer: Save Your Butt With DOS: Part Three

Here's a boatload of great files to finish stocking your DOS toolkit!

DOS's days are numbered, and that's mostly a good thing: In normal operation, a well-developed graphical user interface (GUI) is much easier to use than a command-line interface (CLI).

But when things go wrong with your system -- badly wrong -- sometimes you can't get to the point where your GUI loads. All the GUI-based tools in the world won't do you any good at all if you can't run them. Worse, sometimes an entire hard drive can become unbootable. If all your diagnostic and repair tools -- GUI or CLI -- are on your hard drive, you're toast.

That's why it's smart to have easy access to a bootable DOS floppy and a custom DOS toolkit. In fact, if you rely on your PC for your work or for important personal information and use, I'd say having a bootable floppy and toolkit is an absolutely essential safeguard.

Trouble is, Microsoft is inexorably moving to the day when all versions of Windows are DOS-free. Indeed, Windows 98SE may be the last version of Windows in which you can easily make bootable DOS floppies!

This series of WinMag "Explorer" columns is about ensuring that you'll always have access to useful low-level diagnostic and repair tools that can help get you out of even the worst jams: a complete and practical DOS toolkit you can store in a safe place against future need -- even if, or when, you eventually end up using a DOS-free version of Windows.

Part One of this series set the context and gave the essential ground-zero information; it also contained a plethora of DOS-related links to get you started. Part Two detailed how to create a custom boot or "emergency" disk -- a better boot disk than the one that may have come with your copy of Windows, or that you can make via the Control Panel "Add/Remove Software" applet.

Now it's time to finish stocking your DOS toolkit. In each of the first two columns, I invited readers to post their suggestions for items to add to a DOS toolkit, and many of you did so (thanks!). If you haven't seen the posts yet, click over to the discussion areas for Part One and Part Two to take advantage of the good information there.

Many more readers choose to write to me directly, by e-mail. That's fine (and I thank everyone who wrote in!) but the drawback to e-mail is that it's a one-to-one conversation. So in this column, I'll present the best of the e-mailed reader suggestions so everyone can benefit.

All the following tools are worthy and almost all are available for free. Depending on your system, your setup, your skill level and your anticipated future needs, you can pick and choose among these to stock your DOS toolkit as you see fit: Copy the files that interest you to floppies or a Zip disk, or burn them on a CD. The key thing is to store them in a stable, safe location, preferably not on your hard drive (where a system crash could take them out).

When you're done, your custom boot disk and DOS toolkit will give you more control over your system than ever -- even if Microsoft chooses to completely kill DOS in the future.

And now, the tools:

  • Diag detects, tests and benchmarks your system including 84 Chipsets, 1307 motherboards, 173 processors (through 4 methods), 13 BIOS brands, 62 PC-types, 25 network cards, 21 soundcards, 10 mouse types, 41 partition types, 1400 PCI cards, and more.
  • Cachchk5 identifies and tests the size and speed of your motherboard's cache.
  • Rosenthal System Monitor 5.0 is an automated diagnostic that evaluates hardware and configuration at startup.
  • Two Free Boot Managers: If you want to install more than one operating system on your PC, you need a "boot manager" to let you choose, at boot-up, which OS to run. Some OSes (such as Windows 2000, and many versions of Linux) come with a boot manager, but others (Windows 9x and DOS) do not. XOSL, the Extended Operating System Loader, is a free, slick and full-featured boot manager available from But if all you're looking for is a basic boot manager, look at the free tool available via
  • Partition Resizer 1.33 is similar in function to PowerQuest's PartitionMagic: It's designed to let you resize/move your FAT16/FAT32 partitions safely and without data loss. It's not as fast or as polished as PartitionMagic (which I rely on when I need to repartition a disk), but Partition Resizer is free, and it's hard to beat that!
  • Eight LFN Tools is a set of DOS tools that supports Windows' long filenames. On its own, DOS stores names in an 8.3 format -- a maximum of eight characters, a period, and a three-letter file extension. For backwards compatibility, Windows normally handles long filenames in two parts: an 8.3 fragment that DOS can understand, and a separately-stored remainder of the long name, up to a total of 255 characters. Windows stitches the two parts together, but on its own DOS sees only the first part. This is why a file with a Windows name like THISISAVERYLONGNAME.DOC will show up in vanilla DOS as "THISIS~1.DOC." If you move or rename "THISIS~1.DOC" in DOS, the long portion of the filename will be lost, and the file name both in DOS and Windows will thereafter be "THISIS~1.DOC." Not too good.

    LFN Tools steps around this DOS limitation with a free set of custom-written utilities that uses (and preserves) Windows' long file name format in DOS. The tool kit includes:

    LCOPY: copies files and/or directories (similar to XCOPY)
    LDIR: displays a directory
    LCD: changes to a directory
    LDEL: deletes a file
    LCHK: drive information
    LREN: renames a file
    LMD: creates a directory
    LRD: removes a directory

    You can grab the full set of tools for free here, or see all the programmer's ("Odi") offerings at

  • XMSDSK.EXE is a free RAM disk written by Franck Uberto in France. A RAM disk is a pseudo-hard drive (with its own drive letter) that lives entirely in your RAM chips, and remains active for as long as your system is powered on. Because there are no mechanical parts, a RAM disk is super-fast and can be useful for carrying out disk-intensive operations that normally would leave a hard drive churning: On a RAM disk, even the most disk-intensive operations fly.
  • UMBPCI is an improvement over Microsoft's "EMM386:" Due to memory architecture limitations that date back 15 years, some "upper memory blocks" (UMBs) in the address range between the top of a PC's standard memory (640K) and the start of extended memory (1MB) normally goes to waste. With the right software, these UMBs can be recovered and put to use. The usual way to do this is to include two lines in your Config.Sys:


    The first line loads EMM386, which is a driver for a very old technology called "Expanded Memory." Few apps use Expanded Memory any more; almost all (including Windows) use "Extended Memory." Because almost nothing uses Expanded memory, you add the command "NOEMS" to tell the Expanded Memory Manager that you don't really want any Expanded Memory Services.

    That sounds dumb: loading an EMS driver and then immediately turning off its EMS functions. But the EMM386 driver also gives your system access to the UMB area, and the "DOS = HIGH,UMB" line then starts to put this otherwise wasted memory to use. Thus, by loading EMM386 and turning off the Expanded memory functions via NOEMS, you gain access to UMBs that otherwise would go to waste.

    Still, that's clumsy. UMBPCI is a faster, more direct and better way to access UMBs without the rigamarole of adding and then immediately disabling an obsolete Expanded Memory Manager. It's a power tool aimed at knowledgeable users, and you'll find full info at

  • 3 Free DOS Utilities: FINDIT (a file finder), DEL-it (search for and delete file) and ACCR (ASCII Control Code Remover) are freeware programs by Steven F. Daniel. (requires free registration to download)
  • Apicd214.exe is a self-extracting Zip file containing a generic CD-ROM driver (and instructions) that will work on many systems. If you can't find Microsoft's generic drivers (Oakcdrom.sys or Nec_ide.sys) try adding this driver to your Config.Sys.
  • SHSUCDX is a free DOS-level replacement for MSCDEX, the Microsoft CD-ROM extensions for DOS. Both give you access to your CD from DOS, but unlike MSCDEX, SHSUCDX is part of a comprehensive package of DOS-level CD ROM tools that let you cache, emulate, redirect and share one or more CDs among anything from one to 48 simultaneous users.

Related resources:

By the Bootstraps

A Bevy Of Boot Disks

But Wait, There's More!
Reader Dev Teelucksingh has pulled together a page that lists many of the above DOS tools, plus lots more. And there are many sites offering a world us DOS software including:

With the resources above, plus those listed in Parts One and Two of this series, you can create an absolutely awesome DOS toolkit! Now please click on over to the discussion area and share your best DOS toolkit files, tips, tricks, and tweaks; or ask your DOS questions. See you there!

To discuss this column with other readers, please visit Fred Langa's forum on the Listening Post.

To find out more about Fred Langa, please visit his page on the Listening Post.

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