Windows fails to mount USB drives when they're inserted - a solution

This might actually be useful to people other than people who know me, so I’ve split this article into two:

Short version

If Windows notices USB drives when you plug them in but they don’t appear as drive letters, try installing this.

Long version

The tumbleweeds are really starting to set in on this blog, aren’t they? I really need to get something to post, but what with twittering and now using Google Buzz, I’m finding less need to write anything here.

Still, every now and then I have something to post and it might be useful to share in case anyone else has problems.

My laptop has for some time had problems mounting USB drives. I’d put the USB stick in, Windows would notice it and “install drivers”, but then no drive letter would get mapped. If I really dug about inside “Manage Computer” I could manually assign a drive letter to it but even that would only allow cmd.exe to see the drive, never Explorer or any other Windows program.

After a huge amount of dead ends followed, it turns out the culprit was a broken installation of Daemon Tools. Even though it wasn’t showing up, it seems as part of the install it also installs some kind of global storage filter, provided by a company called Duplex Secure.

I discovered I could fix the problem by simply attempting to install the latest version of Duplex Secure’s “SPTD” from their download page. As part of the installation it first disables and removes any pre-existing SPTD filter, before asking you to reboot and retry installation. I simply let it disable and remove and then rebooted. I didn’t go on to reinstall as I don’t need it.

So now I can plug in my USB drives again and access the data on them! The reason this had become so important is I’ve finally caved in and bought a digital picture frame and I wanted to mount its internal drive to copy my pictures onto it.

Filed under: Blog
Posted at 17:35:00 GMT on 13th February 2010.

About Matt Godbolt

Matt Godbolt is a C++ developer working in Chicago in the finance industry.