I have struggeled a lot with a crazy weird issue. I have a Supermicro server, 16x2,5 drives in Raid, LSI Megaraid. Server connected by a 82599 10Gbps network adapter to a Cisco switch, and 1Gbps to clients. To all my Windows 7 clients a get transfer speeds 115MB/sec. To my Windows 10 clients I only get ~45MB/sec. I was certain this had to have something to do with the windows installation, SMB signing or similar. But after a total re-install of the server, it behaves the same. So in total confusion I tried connecting the server by the 1Gbps onboard adapter (Intel I350) to the switch, and voila, 115MB/sec to both Win7/10-clients. This is of course not a solution since I need the 10Gbps bandwidth to my 9 clients. So to my big surprise it seems to be something fishy going on with the Intel 82599 adapter and Win10 clients, any ideas ? Laters drivers installed. I have tested with default settings, tried the different profiles (standard, lo latency, web-server) and other settings a little randomly based on other comments online, but to further improvements.
For the record, I also have a couple of old Win2008 servers and these provide ~115Gbps to all clients.