SpinRite deleted Drive letters on Windows

  • SpinRite v6.1 Release #3
    The 3rd release of SpinRite v6.1 is published and may be obtained by all SpinRite v6.0 owners at the SpinRite v6.1 Pre-Release page. (SpinRite will shortly be officially updated to v6.1 so this page will be renamed.) The primary new feature, and the reason for this release, was the discovery of memory problems in some systems that were affecting SpinRite's operation. So SpinRite now incorporates a built-in test of the system's memory. For the full story, please see this page in the "Pre-Release Announcements & Feedback" forum.
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  • BootAble – FreeDOS boot testing freeware

    To obtain direct, low-level access to a system's mass storage drives, SpinRite runs under a GRC-customized version of FreeDOS which has been modified to add compatibility with all file systems. In order to run SpinRite it must first be possible to boot FreeDOS.

    GRC's “BootAble” freeware allows anyone to easily create BIOS-bootable media in order to workout and confirm the details of getting a machine to boot FreeDOS through a BIOS. Once the means of doing that has been determined, the media created by SpinRite can be booted and run in the same way.

    The participants here, who have taken the time to share their knowledge and experience, their successes and some frustrations with booting their computers into FreeDOS, have created a valuable knowledgebase which will benefit everyone who follows.

    You may click on the image to the right to obtain your own copy of BootAble. Then use the knowledge and experience documented here to boot your computer(s) into FreeDOS. And please do not hesitate to ask questions – nowhere else can better answers be found.

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New member
Sep 25, 2020
Hi Steve,

I just attempted to run the latest of SpinRite.exe from the prerelease page. I inserted a USB drive into the system before clicking SprinRite.exe, asked for the USB drive to be removed. I removed the USB drive and reinserted. Upon reinsertion Windows 10 locked up.
I reset the computer (hit reset button) and I lost my drive letters from the 3 drives/partitions, I have attached to the system. Perhaps I should have waited for the system to respond correctly, but.... impatience ensued.
I'm using as USB extender cable to insert the USB drive, and at times doesn't connect the USB inserted correctly, ie "there is some play in the connector"
Perhaps someting to debug?
Howdy @rowdy! I'm unsure what I would debug, or what there is to debug. This USB remove/insert approach has been quite well tested. Windows, since the first appearance of USB drives, has never dealt very well with USB, nor with removable media. But many thousands of people have used this approach without any problem. For example, this is the same technology that ValiDrive uses and we're approaching 200,000 downloads of it without any reports of such trouble. It isn't my intention to pass the buck here. If there was anything I could change I would. But software is always at the mercy of hardware. You say that you're using a USB extender cable that's flaky (my term) and that...
at times doesn't connect the USB inserted correctly, ie "there is some play in the connector"
Since setting up a SpinRite boot drive only needs to be done once, my suggestion would be to not use an unreliable USB connection the one time it matters. Once you get SpinRite to setup that drive, all should be good! (y)