For example did you turn the following off? Where's the IT staffer for such a big shop?
Read https://www.howtogeek.com/224981/how-to-stop-windows-10-from-uploading-updates-to-other-pcs-over-the-internet/
Our office has around 15 PCs and all of them uses D-Link DWA-548 Wireless N PCIe Adapter to connect to wifi.
When I turn on my PC the internet connection on my PC and PC next to me get very slow.
No other PC in office get affected.
All of us connect to same wifi router.
If one of the PCs turned off Internet goes back to normal speed in the other PC.
We don't have any download programs in our PCs.
When i check resource monitor don't see any program downloading lot of data.
My PCs have Window 10 Pro and the other computer has Windows 10 Enterprise. I have Avira virus guard free version installed in my PC.
Can anyone suggest how to fix this problem.

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