If this happens often, you can disable write caching for that drive. It'll feel slightly slower (since it's actually operating at the speed of the hardware instead of caching operations in RAM and gradually writing them to disk in the background), but you'll be able to remove the drive almost instantly.

[–] kattfisk@lemmy.dbzer0.com 1 points 6 hours ago (1 children)

Shouldn't that happen automatically if the drive is identified as removable? And the real solution should be to tell the OS that it's removable?

[–] Quetzalcutlass@lemmy.world 1 points 2 hours ago* (last edited 2 hours ago)

I was having terrible performance problems in Windows a while back, and it turned out it had marked every drive as removable, and the write cache was filling up due to an extremely slow external HDD, causing even the internal SSDs to grind to a halt until the buffer was flushed whenever a large amounts of writes were made to the HDD (which was often, since it was used for backups and large Steam games).

[–] DrMartinu@lemmy.dbzer0.com 19 points 13 hours ago

I used to find it had something to do with the explorer thumbnailer finishing up but sort of not letting go. It would happen if I had pictures or videos on the USB drive, and if I got the error I could go to another folder like my documents, drag a picture into another folder, go look at the pretty new thumbnail, then I could remove the USB drive because the thumbnailer was 'parked' back on the C drive. Sounds like I'm making it up but I swear it worked.