Solve slow data traffic on the local network?

Hello,

When workers access a specific drive, it sometimes takes quite a long time. But it has nothing to do with the volume of access. Programs load more slowly, errors occur, etc.

I've tried swapping cables, different ports, different devices, and various other things. The only thing that works is when I unmount the drive using a script and then remount it.

There are currently 300 Windows computers in the network, in an intranet network, the file server is a Windows 2019 Server.

The drives are mounted via GPO.

The devices are Windows 10/11.

Does anyone have any idea what could be causing this?

Thank you for any answer!