CheckIt, from TouchStone Software Corporation, is a diagnostic tool for generic PC/XT/AT compatible computers. It can perform tests on RAM, hard disks, video cards, floppy disks, motherboard resources, and I/O devices. It has an easy to use menu interface but can also run tests non-interactively. It was followed up by the product WINCheckit.

CleanSweep, from Quarterdeck, is a utility that assists with uninstalling and removing leftover files. It also moves programs from one drive to another, to a backup that can be restored later, or to another computer.

Colorado Backup is the software provided with HP Colorado tape drives.

FastFiler, from Ziff-Davis Publishing Company and Strange Software LTD, is a rudimentary easy to use file manager shell. It was sold alongside Computer Shopper magazines. While it offers a friendlier interface than the DOS command prompt, it has fewer features and abilities than competing file managers.

RAM Doubler is a utility for Windows 3.1 that uses advanced resource management and memory compression techniques to allow more applications to run side by side. It was designed to be simple and easy to use compared to some competing programs. It competed against similar tools such as SoftRam, Hurricane, and MagnaRam

Conner Backup Basics is a dumbed down version of Conner Backup Exec that only works with their tape drives. This software will not run at all without the appropriate tape drive attached.

Control Room is an all-in-one resident system information and configuration tool. It includes a number of disk utilities such as undeleting, wiping, and encrypting files. It can scan files and detect unwanted changes. Control Room can change system settings such as keyboard repeat rate and supports creating keyboard macros.

Copy II Mac is a tool for copying copy protected disks on the Apple Macintosh computer. It also includes MacTools, an enhanced file manager with disk editing and testing abilities.

Central Point Copy II PC is a disk duplication program that can successfully copy many copy protected disks using only standard IBM PC hardware. It is generally considered the best software-only solution for duplicating such disks. "snatchit".

CopyWrite is a disk duplicator that can duplicate disks with many advanced copy protection schemes using a standard IBM PC floppy drive and controller.

Correct Grammar is a grammar checking and analysis tool for DOS. Correct Grammar incorporates technology from the Houghton Mifflin CorrectText system.

CorrectStar, from MicroPro International, is an add-on spell checker for WordStar 3.3. It was sold both bundled with WordStar and separately. Later versions of WordStar integrated the spell checker.

Dashboard for Windows, originally from HP, is a convenient push-button utility which gives you quick access to and maximum control over your Windows programs. and buttons for launching programs. Drag-and-drop support for printing, plotting, and faxing. Miniature screens that make it easy to work with several full-screen programs at once. An alarm clock with a built-in snooze alarm. And "At a glance" feedback to let you know which programs are running and how much memory you are using. It has a resemblance to the Unix Common Desktop Environment toolbar.

PowerQuest DataKeeper 3.0, formerly from HighPoint Technologies, is a powerful real-time backup program. It features the ability to continuously monitor backups, works with any removable media, compression, and registry protection.

DECTalk was a text to speech system used in automated telephone, radio, and TV systems. It was notably used as an artificial voice by Stephen Hawking. Most DECTalk devices were standalone serial devices, however DEC did produce an ISA expansion card for the IBM PC that contained this functionality. This software is required to operate these ISA cards.

DevTech's Deskman/2 is a set of desktop and system management tools for OS/2. It contains data compression tools, networking tools, performance monitoring tools, and desktop management tools.

DESQView, from Quarterdeck, was a DOS application multi-tasker and in later versions functioned as an X client for applications on remote UNIX systems. It competed against IBM Topview. The original DESQ was just a task switcher, but subsequent versions offered preemptive multitasking of well behaved DOS programs on real-mode 8088 PCs. It gained popularity when DESQView 386 added virtual x86 support. This enabled the ability to multi task many poorly behaved programs, and was often used on BBSes due to its excellent COM port handling. It was later overtaken by OS/2 and Windows.

Direct Access is an easy to use menuing program designed to simplify access to applications on systems with many programs loaded on the hard drive. It is customizable, includes screen blanking, and includes password protection and usage logging. Later versions also detect common programs already installed on the hard disk.

Disk Technician, from Prime Solutions Inc., is a hard disk utility and surface monitor. It contains an interleave adjuster and pattern tester similar to Spinrite. The Gold version also includes a defragmenter and disk-level virus protection.

DiskClone, from Quarterdeck, is a simple, professional, small, powerful, and easy to use hard disk cloning tool. It can copy a drive to another internal or external drive of different sizes. It can be used as a backup, or a migration tool to a new drive. It all fits on a single floppy disk. "Corporate" editions.

DiskDoubler is an automated file compression program for the Apple Macintosh. It does not compress the entire drive, but rather specified files. It automatically compresses and recompresses files as you use them.

Diskeeper is a professional disk defragmenting tool with versions for both 9x and NT. It includes features such as scheduling and background defragmentation.

Diskette Manager, from BLOC publishing, previously from Lassen Software, is a software tool for the IBM PC and Tandy that inventories the contents of your floppy disks in to a database. It enables you to quickly and easily search for files or print disk labels.

DiskLock, From Fifth Generation Systems, and later from Symantec as Norton DiskLock, is a data security tool that can lock a hard disk or individual files or directories so that it requires a password to access any data. It can also log activity to detect unauthorized access attempts. It also features the ability to lock the system after an idle usage period. There were versions for PC and Mac.

First released in 1989, DoubleDisk was the first real-time drive compression product for DOS. It is a fairly no-frills program and sticks to what it does best. It was relatively low cost compared to its later competitors. and Expandz! Plus