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For whatever strange reason the task manager on my current Windows 7 machine is not monitoring the amount of data send/received correctly. Is this a known bug or where are my bytes secretly hiding?

enter image description here

I just downloaded a 100MB test file and clearly more than 416 bytes have already been received. Under options I activated "Tab is always active" and "Show cumulative data" but neither changed anything.

Update: to add insult to injury, after rebooting even the numbers between Sent/Received and total do not match up anymore. Bytes send shows 483, Bytes received 1 and Bytes 2.

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My first guess was that you have selected the Bytes Recieved per Interval Then I saw the second column on your screenshot.

My second guess is that it's a factor of a Wireless NIC as I tested a download with a physical NIC on my machine and the value increments as expected.

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That the wireless NIC fails to count correctly might be the reason. I did not record seeing this behavior on any computer via normal ethernet. Maybe it is also the driver of this specific wireless NIC. At the moment it is just annoying so I won't buy another NIC just to test this theory. – Alexander Feb 28 '13 at 13:11

The Task Manager only displays data accumulated since it opened up. Download the file with Task Manage open and on the page you screenshotted and you should see the activity.

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I opened the Task Manager before starting the download. The screenshot shows the download progress after a few MB already transferred. Now after the 100 MB file is completely downloaded "Bytes received" says 454. The Task Manager was open and running the whole time. – Alexander Feb 27 '13 at 19:18

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