In reply to a post by robertcrowther:

It doesn't look to me like a driver or third party software, it does however show classic symptoms of either an IP address conflict, or I have seen in the past where laptops will still try and use wireless connection even though the ethernet is plugged in

Yes, good points, and very likely, although Win10 is usually cleverer than that!

On Windows 7 and Windows 10 if a computer is connected to the same network by both Wi-Fi and gigabit wired, Windows will prefer and use the wired connection by assigning a better (lower) metric to that network adapter - use the "route print" command to confirm this.

The priorities can be manually re-ordered and some people do this intentionally or inadvertently when trying to solve some other problem, such as if they want to override a wired connection while tethered to their smartphone.

The situation might be different if the wireless channel width is configured so wide and the laptop and AP have enough spatial streams that the link can report a data rate faster than 1Gbps but this is an edge case.

On the IP conflict thing, if DHCP, one or both PCs will release the IP and restart DHCP discovery.
Checking for IP already in use on the network (ARP) before making an offer is part of the protocol, even if the DHCP server doesn't think it has already leased this IP.

Even if manually assigned IPs and conflicting, on the affected computers Windows would normally popup an alert as well as a flag on the network icon in system tray (in older versions at least).

And if there was an IP address conflict they would still have problems copying files to and from the NAS, because the affected computers would be constantly trying to assert "I have the L2 Ethernet address for that IP" (ARP), even if the second computer was not the source or destination of the file copy.


TL:DR (Wi-Fi?) you don't have to guess because you can run the command to check

Edited by prlzx (Sun 21-Jun-20 12:12:40)

Windows has always been utterly dire when copying large numbers of files (to be fair, other OSes suffer somewhat as well). There appears to be a bad overhead when it comes to finding and opening files. However the raw throughput is usually fine. So if you're copying large numbers of files (especially small files) it is a lot, lot better to compress them to an archive first.

https://docs.microsoft.com/en-us/windows-server/stor...

Edited by Andrue (Sun 21-Jun-20 12:05:39)

In reply to a post by prlzx:

On Windows 7 and Windows 10 if a computer is connected to the same network by both Wi-Fi and gigabit wired, Windows will prefer and use the wired connection by assigning a better (lower) metric to that network adapter - use the "route print" command to confirm this.

Not sure you meant to reply directly to me, but I’ve known this since Windows 3.11 for Workgroups with multiple ethernet adaptors, long before WiFi

Edited by jchamier (Sun 21-Jun-20 13:38:59)

In reply to a post by Andrue:

Windows has always been utterly dire when copying large numbers of files (to be fair, other OSes suffer somewhat as well). There appears to be a bad overhead when it comes to finding and opening files. However the raw throughput is usually fine. So if you're copying large numbers of files (especially small files) it is a lot, lot better to compress them to an archive first.

https://docs.microsoft.com/en-us/windows-server/stor...

Or use robocopy with multithread option - that will normally allow you to maximise the network link.

Yes sorry,

I was responding to Robert's suggestions about Wi-Fi and/or IP conflicts however in doing so I was expanding on your comment that "Win10 is usually cleverer than that!" so my reply needed to follow that thread to stay in context for the sake of the OP following the suggestions.

I've viewing in flat mode so usually just bottom posting anyway, but I'll try to make better use of selective quoting and reply@who hints.

Edited by prlzx (Mon 22-Jun-20 01:55:22)

In reply to a post by prlzx:

I was responding to Robert's suggestions about Wi-Fi and/or IP conflicts however in doing so I was expanding on your comment that "Win10 is usually cleverer than that!" so my reply needed to follow that thread to stay in context for the sake of the OP following the suggestions.

Thanks for the update!. I read somewhere that the speed of the connection would also influence. I remember setting interface metrics.

(I prefer netstat -rn but you get the same table)

In reply to a post by jchamier:

In reply to a post by joconnell:

Has anyone else encountered similar issues with Windows 10 PC-to-PC networking?

Yes, with Symantec, McAfee or any other third party antimalware installed. Do you have that sort of software?

If you don't and are just using Win10 with its built in Defender, then it could be a network card driver issue.

Given the PC to NAS is quick, but PC to laptop is slow, the problem could be the laptop writing to its disk?

It's the same issue whether copying files from the laptop to the PC or vice versa - both machines have SSDs so I'd be very surprised if that's an issue.

In reply to a post by robertcrowther:

It doesn't look to me like a driver or third party software, it does however show classic symptoms of either an IP address conflict, or I have seen in the past where laptops will still try and use wireless connection even though the ethernet is plugged in

Wireless on the laptop was switched off so only ethernet connection

Well there are no less than 7 ethernet adaptors showing when I do ipconfig in a CMD shell, though there's just one wired NIC on my desktop PC. The others are for things like Hyper-V, Neorouter, Kaspersky, NordVPN but only the Hyper-V and Realtek NIC ethernet connectons are enabled, there seems to be nothing I can do about the Hyper-V adaptors unless I uninstall Hyper-V