I've been having trouble with downloads and updates for months. They say it's mostly an issue for older OS, but it also happens on both Windows 10 and 11.

There is so many publisher sales atm, try switch steam DL zone.

Also sounnds like into steam issue and thats your ISP problem.

and you already mention Antivirus app, but check blocked or qurrantine folder

i know windos defender use block.exe. se windows defender own app.

make sure steam.exe is on allow or exception.

and win 7/8 has also been mention so you are on TOP on all current event.

Try other pc even , nothing prevent you from use a usb stick as test or transfer media, to proof its my own pc that has a issue.

ps.
this is what tech dude due we try proof its steam or ISP or my own pc that has a issue we have not solve with what. ( you name it security, or other odd issue , but 98% same place look more like a security app blocking issue diffrent %% then its a lack of free space maybe or other check drive issue. ( windows has check disk and steam hgas repair steam libray , but now we are grapsing for structure issue, they can happedn but is so rare, that most will say never that.

Dont come here with own system issue. ( well maybe you do hope this is the issue, because most here can tell if its not, you are in trouble with a hardware or software issue , most atm cant see what cause this.

DISM.exe /Online /Cleanup-Image /Restorehealth
SFC /Scannow
chkdsk c:
chkdsk d:
chkdsk e:

you have been several other crasy ideas, i and other dont care if spare pc or freinds laptop work at your place then you do have narrow down it at own pc issue, but with what. even that help.

exatly what pros do, point fingrs at what pc cause this, and let local IT department fix local pc issue, its not preety always , but be glad you gor a narrow down who is the cause, no matter where fault is.

you need to understand i look at things diffrently from a network point of view, we try to eliminating the problem thats cause issue. and we have to be tough and rude, because if we arer not this , you can kiss global internet byebye. ( sometiems we even replace device jsut to make sure its not a hardware isue, i know you might not have suchj option but point is made how fare we try to go.

gl with it,

dont forget you have steam support
that game devs that made it. ( upload content that do not work )
and own ISP into steam issue

ps.
what are the odds its game devs content thats slim but also seen before.

I'm not trying to come with my own system issues, i wanted to know if anyone else is having these problems (obviously, they do), if there is some current steam download issue or if really is my PC. I did try the download on my other PC, same thing, I just don't understand why the download always stops at 660,34 MB. Always. Until this file size the connection and download is flawless. Is my cloud full or corrupted?
Support says it seems like server issues, I just don't understand how every server would stop at that particular file size and wanted to know if anyone is having same issue and maybe could help. I mean really, resuming doesn't work, but why does the download work up until that file size?
Simply because it's first time this is happening, all other games I purchased before downloaded and work well and I didn't change anything on my PC settings.
I am not a tech. I simply wanted to buy and play another game...

I'm having exactly the same issue. 660.4 MB and the download stops.