Why is my download stuck at 100%

[certified freaky]

An update i am downloading (something like 30 MB) is stuck at 100%, and won't complete.
Edit: I assume it is about the disk usage, but i can't seem to increase it without pausing and resuming the download. Any way i can fix this?

[Yasahi]

Let it work. Your disk is working, applying the update.

[Iceira]

Anti virus blocking issue, thats why.

[HandMeat]

So this is what I'm here to find the "Why" of today, that time frame your referring to is the download being "committed" to the rest of the game.

I downloaded a DLC map for ARK, which is installed on a 250GB SSD (Drive F:) and the only thing on that drive. My C: drive is set as default library drive/folder, and is a 1TB NVME SSD. I should also note that I have a fiber connection and have seen an actual gigabit connection speed inside of windows task manager(which I didn't think was possible). Anyway....

When I installed the map, which was only 5.7GB, Steam decided to download it first to my 4TB HDD(Drive B:). So, rather than being able to utilize My super fast internet connection or plethora of high speed storage options, I had to first wait the half an hour for it to download the game (limited by write speeds of the HDD), then I had to wait another 10-15 minutes for it to copy the file over (this time limited by the read speed of the HDD).

Now, I have quite tediously looked at and clicked on every single option and button in the settings menu and elsewhere and can find NOWHERE where this is configurable; I do, however have some theories.

Theory Number the First - Windows did it.

--When I downloaded the game initially, it zipped through the first 20 or so GB's but then the SSD ran out of it's higher speed NAND cells (used for initial caching of writes before they are moved to more permanent but slower NAND cells) and it crawled through the last leg of the journey. It was only about an hour in between downloading the base game and downloading the DLC so mayhaps Windows said 'Nay, let this drive think, use this other one that has all of the available space as a staging location' then committed the files afterwards.

Theory Number the Second - There's something going on with the download manager/scheduler/

-- Not much else to say other than I think it's using bad/flawed logic to choose a 'Staging Location'.

I can see and appreciate the need to download something like a DLC (which alters the game files) to a temporary staging or quarantine location until the download finishes, and the new content can be inspected before merged into the existing game files (preventing potential damage to the base game if the DLC got broke in transit). What I want to know is how do I tell steam to go use the faster (or at least same) drive for this? Why and How can I prevent the choosing of the ONLY mechanical drive in my system, short of removing the drive? Can we have a settings menu item added for this?