I see part of this is a known, old issue: https://www.dropboxforum.com/t5/Dropbox-files-folders/Thumbs-db-files-stops-uploading-process/m-p/17...
But since its reply/solution was ludicrous, i.e., that one should delete files named thumbs.db prior to uploading, I thought I'd bring it up again. Plus, the same thing happens with files named 'desktop.ini'
I did not read the thread linked to in that old thread's so-called solution. Why not? Because I DON'T CARE what Dropbox's reason is!
What I do care about is that I'm paying GOOD MONEY for this service. I also care that I have hundreds of thousands of files, spread across thousands of sub-directories on assorted computers and devices.
Being a Linux-only person, and really good at shell scripting, I'm perfectly capable of writing a script to recursively find, and delete [rename, move, etc.], all files named 'thumbs.db' and 'desktop.ini' [with all variations of case, since *nix is -truly- case sensitive]. But I WON'T do that.
Whatever asinine reason Dropbox has for not accepting thumbs.db and desktop.ini files, doesn't make -my- thumbs.db and desktop.ini files expendable. They cannot arbitrarily be deleted just because a service I'm PAYING for has deemed them forbidden.
Assuming Dropbox uses files named 'thumbs.db' and desktop.ini as part of its processing, and doesn't want conflicts with customers' files with the same name, what they should do is change the name of THEIR file. Instead of the common 'thumbs.db' and 'desktop.ini' use something unique to Dropbox, like dropbox_0123456789_abcdefg.db [in other words, something so unusual, so bizarrely unique, the odds of a customer ever having a like-named file are infinitesimal]. Better that odd chance of a one-in-a-billion occurrence than forcing PAYING CUSTOMERS to delete files before uploading.
What about users who aren't very computer savvy? What if they have no idea how to write a script to automate deletion/renaming? What if, like me, they have hundreds of thousands of files? And, like me, their thumbs.db and desktop.ini files aren't expendable?
Dropbox needs to fix this.
I can't imagine by what 'logic' they decided that making millions of people plod through their files, deleting those with certain names--even if they're needed--before uploading, made better sense than THEM using a unique name! My time is valuable. Will DB reimburse me for time used shuffling files around so they'll upload?