BTW, thanks for cutting my search short; me mouse hand was getting real tired, as that's the one with Carpal Tunnel Syndrome!
My 10565 works perfectly with USB ejects. Sorry about that!
@mlhifi. If you want to find what is holding your drive I posted earlier that I found the answer in Event Viewer/System. Find "Kernel PnP id 225".
I am about to re-install 10240 as I know all will be well again... as well as can be expected anyhow, and I also know Rufus plays nicely with Win10 RTM and USB eject works everytime.
At the same time, I (we) have to remember that as we install these "builds" they are like Beta's and we shouldn't expect them to work properly. That's what I tend to forget if I'm honest.
So, what next? What IS the problem that is preventing me from safely ejecting my drive and preventing me from using my favourite iso-to-usb program? Rufus in case you didn't get it :-)
official issue tracker, as I only stumble onto these kind of forum posts when actively looking for them... which is rarely. Granted, the issue tracker may not be as convenient or familiar compared to using this forum, but, really, this (or direct e-mail) is the only way you can be guaranteed to reach the author of the application and possibly get an answer to your problem.
Now, if you look at the issue tracker, you'll see that there already exists an issue opened just for that problem, where I also reported that, while buid 10565 has some improvements, it does NOT consistently solve it. I'm hoping that, at some stage, Microsoft will finally get their act together and fix it one and for all, but it's up to them... Still, you can help pushing for this by making sure you report it (or upvote similar issues) in Feedback reports for "Hardware, Devices and Drivers" → "USB devices and connectivity".
Finally, you may want to try a new cheat mode that was introduced with Rufus 2.5 BETA (which you can download here - be mindful that it's not available in Rufus 2.4 or earlier), that disables exclusive drive locking. If you run Rufus 2.5, and press Alt-, on your keyboard (that's the 'Alt' and comma keys), you will be able to toggle exclusive locking, which may help. However, I don't see it as a proper solution (the problem really is with Microsoft), which is why it's only a cheat mode.
Hope that helps.
Yes, for the most part, we here in this thread are in agreement that the fault doesn't lie with Rufus, but with Windows 10 Insider Biuilds. I think that the proof in the pudding is that some of us (not I) have had the problem of ejecting Jump/Flash/Thumb/USB drives early on (or even from the beginning) in the Windows 10 Technical Preview, while for others of us (me) only started experiencing it with Build 10547.
Rufus didn't cause the problem with Windows 10; Windows 10 caused the problem with Rufus! If Windows 10 will "safely eject" the USB drive, then Rufus will work flawlessly. I would ask the detractors to prove differently.
I will jump onto your Beta, as I'm a long-time beta tester of Microsoft products. Yeah, I know the pitfalls, and if I get into trouble, I can always reinstall Windows 10 Build 10565. Windows 10 Insider Builds were made to reinstall.