2 external drives copy G to H

[callasda]

When updating additions on G to H

Cannot copy file
"G:\IRELAND JOHN 1879-1962 british composer\THE HOLY BOY.flac" to
"H:\IRELAND JOHN 1879-1962 british composer\THE HOLY BOY~954a.ffs_tmp".
ERROR_IO_DEVICE: The request could not be performed because of an I/O device error. [CopyFileEx]

Cannot read file attributes of "G:\".
ERROR_PATH_NOT_FOUND: The system cannot find the path specified. [GetFileAttributes]

Then when exiting, both drives disappear from the list

[xCSxXenon]

Sounds like "G" is failing or has a spotty cable