Strange problems with a network folder?

Question

Computer networks

We allocated a computer for a file server, everything seems to be set up well, but for some reason on half of the computers the network folder opens for an extremely long time on the other half, everything is lightning fast, the folder is used by ~ 10 users at the same time. when this network folder was on another server, everything was fine and there were no such problems.

Answer 1

Download iperf for windows and check your network throughput.
If there is a blockage (< 980 Mbps), look for a problem - it is either in the settings or in the equipment.
If in the equipment - most likely, the dead switch is guilty.
If in the settings - for sure someone twisted the MTU and screwed it up.

Answer 2

what OS on the server and on the client?