Hi

I have recently bought a Win8.1 machine. I am using my wi-fi connection (450mbps) to copy files from my old Win7 PC to the Win8.1 PC. However, when I try to copy large files (avi's etc) the copy speed drops from c. 20MBps to 300-500k per second. The Win7 PC is connected via a CAT5e cable.

I have tried disabling all security software, restarted my router (to which both PC's are connected) to no avail.

I copy my iTunes library (600GB) in about 8 hours. When I select a 17GB avi it says it will take more than a day and the speed drops to half a MB or less. Is there anything I can do to fix this issue, please. Copying large files when using WinXP was a breeze!

Scrap that bit about file size. It seems to happen with any size video file - avi, mp4, flv.... The transfer speed drops ridiculously.

Hi The RealBlood,

Please provide more information for better analyzation:
1.Does this issue occur when you transfer large file like .zip? Will this occur when we compress the video file to zip file?
2.Does this issue only occur when transferring file from Windows 7 to Windows 8.1 or also in the other direction?

We could set Large Send Offload v2 (IPv4) and Large Send Offload v2 (IPv6) disabled, and then check if the issue exists.

For more information, please refer to the following thread.
http://social.technet.microsoft.com/Forums/windows/en-US/c30f6649-a0d9-4f5e-8671-904a8f5469bb/windows-7-ultimate-painfully-slow-file-transfer-on-ethernet-network-cables-only?forum=w7itpronetworking

Best regards,
Fangzhou CHEN

Hi

Thanks a lot for your reply. Since this message was posted I have finished copying data from my old W7 to my new W8.1 and the W7 machine has been retired so I can't do any further testing.

Thanks again.

• Proposed as answer by Michael ShaoMicrosoft contingent staff, Moderator Tuesday, September 30, 2014 11:23 AM

Hi

Thanks a lot for your reply. Since this message was posted I have finished copying data from my old W7 to my new W8.1 and the W7 machine has been retired so I can't do any further testing.

Thanks again.

• Proposed as answer by Michael ShaoMicrosoft contingent staff, Moderator Tuesday, September 30, 2014 11:23 AM

Try

1. From the Run command: ncpa.cpl (or go via Control panel to Network connections)
2. Right click on 'local area connection' > properties
3. Click 'configure' to open new dialog box
4. In 'Advanced' tab: select TCP checksum Offload (IPv6) & select 'Disabled' from drop-down menu.

Can try with WiFi adapter also.