Hi Michael, I'm not familiar with automatic encrypting folders. Is that Windows 10 feature that's easy to turn on?

As you probably noticed, Firefox 98 changed from starting downloads in the Windows Temp folder for "Open with [relevant application]" to starting them in your "Save Files As" folder set on the Settings page. I wonder whether this is part of the issue?

Firefox 102+ has an option to switch back to starting downloads in the Windows Temp folder and I suggest testing whether this makes any difference. (But it does mean that if you "Open" a file then you need to remember to save it in a normal folder that doesn't get cleaned out.)

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

More info on about:config: Configuration Editor for Firefox. The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.

(2) In the search box in the page, type or paste browser.download.start_downloads_in_tmp_dir and pause while the list is filtered

(3) Double-click the preference to switch the value from false to true

(I don't recall whether that takes effect on your next download or after you next close and restart Firefox.)

Hi, Thanks for taking time to help solve this problem. Windows EFS (encryption file system) has been around for a while. When you right click a file or folder, there's an advanced button which gives you the option of encrypting the file, folder or the folder, sub-folders and all files within. When a file is added to an encrypted folder, it automatically encrypts. I tried your solution, but it didn't work. I did try to copy a random unencrypted file into my statements folder and it encrypted as expected. In my efforts to solve this, I have already checked if this was a Windows problem. Didn't find anything. But when I tried using IE, it worked. There must be a Firefox change in the "web download file" operation that doesn't account for Windows file attributes.

Thanks, Michael W

Aha, yes, EFS is locked out on our systems, but I remember it from the XP days.

I don't know whether the problem is that Firefox doesn't allow Windows to encrypt the file, or Firefox doesn't tell Windows to encrypt the file, or something else.

I didn't see any recent bug reports for this. Do you want to file a new one? https://bugzilla.mozilla.org/