That's strange for a two reasons:
1. It's quite uncommon for a desktop to use WiFi. Try an Ethernet cable in stead.
2. The router doesn't know what you download. It just sends and receives packets without looking at the content. Assuming you have a separate router and modem, try it without the router and connect the desktop or laptops directly to the modem. Any difference?
Additionally, try the laptops with a friend or at work or school. Do they work there? If they do, reset modem and router and try again. If it's in Ubuntu and in 2 different Windows machines, it's unlikely to be a PC issue.
Kees
Hello. This is my problem:
I can't download some .exe files. It looks like it started downloading but it doesn't. In download directory there is a file "Unconfirmed _____.crdownload", where ____ is a number. Sometimes it says network error. It does not help to use other browsers (I tried: Google Chrome, Firefox, IE, Safari) This occured while downloading: Avast, Skype, JRE.
Additionally, when someone send me Skype installation file it couldn't download files needed to install itself.
I can't download it on any computer in my home (desktop with Windows XP, laptop with Ubuntu 12.04 and laptop with Windows 8.1). This lead me to conclusion that this is a problem within my home wi-fi network. Unfortunately I do not know where and what the problem is.
I am using router TP-link tl-wr543G
Can someone help me please?

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