Microsoft confirms large file copy speed issue in Windows 11 2022 Update

Senior Program Manager, Windows Server Engineering Ned Pyle on the Tech Community forum confirmed that Windows 11 2022 Update users may experience a slowdown in copying large files (several gigabytes) from a remote computer. SMB throughput can drop up to 40% in this scenario. The issue does not affect Windows 11 version 21H2.

Pyle notes that the problem is not related to the SMB protocol, so users may experience slowdowns when copying local files as well. When copying data from a remote computer, this problem will be most pronounced.

Microsoft engineers are investigating the bug and preparing a fix. As a workaround, users can use the robocopy or xcopy utilities with the option /J for maximum data transfer rate.