The first release of SpinRite stunned the personal computing industry. Never before had anything been able to "non-destructively" low level reformat a hard disk drive. SpinRite used this totally unique and original capability to adjust the "sector interleave" of MFM and RLL drives in order to optimize the mass storage system performance.

SpinRite was also VITAL for detecting surface defects that were printed on drive labels but had never been manually entered (as was required) by the system's integrator during the initial low level formatting and system setup.

After SpinRite's first 18 months in the marketplace, SpinRite II was developed to respond to all of the feedback we had received from our customers. SpinRite needed to operate upon drive partitions larger than 32 megabytes (Way back then, MS-DOS only ran on partitions smaller than 32 megabytes!) and to advance SpinRite's core technologies on several fronts.

SpinRite II allowed the use of BIOS-extending device drivers, provided enhanced reporting, and incorporated many special handlers for whacky and weird hard disk controllers. SpinRite II was much more compatible with the exploding market for personal computing mass storage.

The release of SpinRite 3.1 -- which was horribly delayed after its announced release in order to incorporate fully integrated support for hard disk partition data compression -- was a nearly complete re-write of SpinRite II.

SpinRite 3.1 broke completely new ground by circumventing the system's BIOS and talking directly to the mass storage system hardware. This paved the way for a whole range of powerful new capabilities. It allowed SpinRite to detect much smaller defects and it enabled the radical Dynastat data recovery system.

SpinRite 3.1's major new features were:

Completely rebuilt user-interface with "smart" default settings that are retained for SpinRite's next session.

Instant Start - SpinRite now remembers technical drive specifications so that future sessions can start immediately.

Operates on multiple partitions or drives in one session.

Easier-to-read detailed technical log in tabular format.

"Rapid Data Recovery" quickly locates, recovers, and repairs damaged areas making SpinRite dramatically faster than ever before.

"Sector Access Velocity" benchmarking technology accurately measures any drive's true performance.

More flexible and useful reporting options.

Advanced technology "DynaStat" endangered data recovery.

Virus awareness prevents SpinRite from being compromised.

Time kept marching on and drives kept getting bigger ... and bigger and bigger. So, SpinRite needed to address these changes for its customers.

Here's what was added to SpinRite 4.0:

TEN TIMES faster operation
SpinRite 3.1 brought newly powerful disk surface defect detection to the end user in the form of "long-period" analysis patterns. Although this approach proved to be very effective in the detection of data-affecting surface defects, we encountered two problems:

First, since each testing pattern had a deliberately long repetition period, each one of the many test patterns could only test "data bit cells" which were spaced far apart. As a result, a great many individually-shifted patterns (typically twenty-two) were required to scrub every possible bit cell. This took an inordinate length of time.

Second, the long-period patterns tended to interact not only with the disk's surface (which we wanted), but also with the read/write electronics throughout the drive's data channel (which we did not want). The result was an effect that we dubbed "the ping pong effect" since SpinRite 3.1 would erroneously mark regions as defective, and then later mark them as good.

Some SpinRite users wondered how defects could "come and go"; since this seemed counter-intuitive. It turned out that the problem was an interaction between SpinRite's intolerance for any variation in data amplitude, even though the long-period patterns had been designed to force just such variations.

No more "Ping Pong."  Faster Testing.
After three years of extensive laboratory and field experience with SpinRite 3.1 we have introduced an entirely new pattern testing technology based upon "short-period" test patterns. The short-period patterns create the required minimum amplitude data signal that's required for detecting weak spots on a drive, but without coupling into the drive's internal electronics. And since these patterns are able to test every other data bit cell, only two patterns are required rather than twenty-two! Thus, we have the delightful side benefit of up to a ten times improvement in overall surface defect analysis performance in SpinRite 4.0.

SpinRite 4.0's defect analysis is now so fast and effective that we even eliminated the weaker and faster surface analysis tests. Rather than three "levels" of surface analysis, now there's only one, because that's all you'll need.

Latest drive technologies
SpinRite 3.1 introduced direct hardware register level awareness of IDE and SCSI drives, but drives have continued to evolve. SpinRite 4.0 again catches up with the newest drive technologies, offering a full working awareness of all current and near-term future drive interface, data transfer, and operating technologies.

MUCH STRONGER data recovery
Though the DynaStat Data Recovery system is stunningly powerful, SpinRite 3.1 users commented that it frequently "took forever" when the drive being worked on (a diskette for example) contained data that just wasn't that precious.

So ... the new "DYNASTAT" command line option allows the data recovery strength to be either turned down to nearly none, or up to 1000% ... for massively strong recovery performance.

Continually predicts completion time
When we introduced multi-partition operation tagging into SpinRite 3.1, we removed SpinRite's original completion time estimation system. This feature was very much missed by users of version 3.1, so we've returned and improved its operation. Now the Graphic Status Display screen, and the moving blanking box, both show the elapsed time and estimated completion time for the current partition.

Quick-Run diskette operation
SpinRite 3.1 introduced SpinRite's advanced DynaStat Data Recovery to floppy diskettes, but still required a burdensome full system reboot. SpinRite 4.0 allows diskettes to be recovered without requiring a clean boot.

The command line option: "DISKETTE" jumps the user directly into SpinRite for operation on the A: or B: diskette drives. Operation on hard disk drives is suppressed, since this continues to be unsafe without a clean system reboot. But diskettes can now be recovered much more easily and quickly. (And with surface analysis that's about seven times faster on diskettes!)

Updated for DriveSpace recognition
Shortly after SpinRite 3.1's release, Microsoft renamed their whole-drive compression technology "DriveSpace." Since the underlying filenames were also changed, SpinRite 4.0 recognizes DriveSpace compressed partitions under DOS 6.xx, and Windows 95.

Intrinsic caching compatibility
On some rare systems, SpinRite 3.1 was unable to operate due to intrinsic data caching that SpinRite could not circumvent. This limitation was completely eliminated by restructuring those aspects of SpinRite. SpinRite 4.0 could then operate upon many DOS storage subsystems where it could not before.

Miscellaneous interactions resolved.
During the three years of SpinRite 3.1's existence, we encountered miscellaneous operational interactions with obscure hardware and software. Rather than pointing fingers, we've simply solved these problems by incorporating various work-arounds. As a result, SpinRite 4.0 was more able to operate with anything it encountered than any SpinRite before.

This crazy industry is never going to stop, or even slow down. SpinRite needed to address Window's new 32-bit FAT format and the proliferation of mass storage alternatives. So SpinRite 5.0 brought many new features to its users:

Operation on FAT32 (32-bit) partitions
SpinRite has been taught all about the newest 32-bit File Allocation Table partition format (FAT32) used in the OEM SR2 release of Windows 95 and 98. Unlike any other disk utilities, SpinRite also knows about the more "arcane" aspect of the FAT32 system, such as the "redundant boot sector" and "current active FAT" facilities. It uses this knowledge to induce even more reliable operation from the system's mass storage equipment.

Compatible with "device-driven" drives
Until release 5.0, SpinRite could only operate upon drives that were directly supported by the motherboard BIOS. This meant that it was unable to operate upon many SCSI and all removable media devices. SpinRite 5.0 manages to overcome this limitation and now operates upon any drives which can be seen from the MS-DOS command prompt. If you can do a "dir" on a drive, SpinRite will be able to recover, repair, and maintain that drive in perfect health.

Special handling for JAZ and ZIP drives
Due to their popularity (and sometimes troublesome nature) special attention has been given to SpinRite's handling of Iomega JAZ and ZIP drives. Elsewhere on this site you will find more detailed references to SpinRite's successes in recovering data from "Click Death" JAZ and ZIP drives and cartridges.

Windows/DOS hybrid program
Although SpinRite still runs from the MS-DOS prompt as it always has, SpinRite can now be launched easily and quickly from Windows because it is also a true Windows application. No longer needing a "PIF" file to give SpinRite an icon, the new SpinRite.exe file is a full well-behaved Windows citizen. It will gracefully shutdown Windows, run itself in DOS mode, then restart Windows after it has finished operation.

Automatic and seamless drive locking
To prevent multiple programs from accessing a drive while under a multitasking system like Windows 95 and 98, individual drives must be "locked" and "unlocked" to give a single program exclusive ownership of the drive's file system. SpinRite 5.0 incorporates this locking and unlocking technology to operate seamlessly under Windows 95 and 98.

"NoBlanking" command line option
There's just no way around the fact that deep pattern-testing of the magnetic recording surface of a hard disk takes time. Despite all the attention this fact has received during SpinRite's ten years of life, it still takes a long time. And, of course, drives are ridiculously larger today than they were back then.

Since the machine will be running for a long time, SpinRite incorporates a built-in screen blanker so that a fixed image is not burning itself into your monitor for hours on end. But some people dislike continually unblanking the monitor to see what's going on with SpinRite. For them we have added a new "noblanking" command line option.

Redesigned low-level IDE interface
As IDE drive speeds continue pushing forward, drives and cables are being sorely tested. SpinRite 4.0 ran into trouble with some drives which caused it to "hang" or take "forever" to complete its drive characterization. SpinRite 5.0 has a completely redesigned low-level drive hardware interface that's designed to prevent any further trouble during drive characterization.

With SpinRite 5.0 still so young, and with SpinRite's typical version lifetime being several years, it is MUCH too soon for us to talk about what will come next, or when. We don't know yet. But as you can see when you look back over the past ten years of SpinRite's life, growth, and evolution, we will continue to respond to developments and changes that occur in the industry. We will always offer the most advanced utilities to provide for the long term maintenance, repair, and data recovery of personal computing industry mass storage systems.