Very slow and erratic data transfer to and from NAS used for backup
Due to heavy work load the past year or so I allowed things to quit working and am now trying to take advantage of being stuck at home to get my systems working properly again. My WD My Cloud NAS isn't co-operating. I use it for back up, so I need to copy large chunks of data to it, and 7 KB/s doesn't cut it.
Netgear GigE switch connected to AT&T router by CAT6 cable. Everything listed below is connected to it by cable, not WiFi.
Old computer (originally Win7) running Win19Pro 1903. Runs very slowly and periodically stalls with excessive disk access. Has my e-mail on it, so I can't retire it until e-mail is moved. Need backup of e-mail before attempting move.
Newer computer with recent fresh install of Win10Pro 1909. Runs great. Need to move e-mail to it. Both computers are Lenovo ThinkCentres of differing vintage.
1 TB WD My Book Live NAS that contains nearly all of my data (except e-mail). I use it as a file server, operating as a mapped drive on both computers. It mostly works okay, but has occasional lapses when large transfers will get rather slow. Oddly, when I tried to get back into the dashboard after many months I can see the dashboard, but choosing any of the menu items just results in a timeout.
3 TB WD My Cloud NAS that I use as a backup server, operating as a mapped drive on both computers. It was working fine when I stopped doing backups sometime last year (long story). Now that I'm trying to get it going again the data transfer speeds are very erratic: occasional spurts at MB speeds, but long periods of speeds in the range of 7-10 KB/s, with additional long periods at zero, triggering timeouts. It doesn't matter which of my two Win10 computers I use to manage the transfer.
The only changes that I can think of that have happened since the last time the My Cloud was working well have been Microsoft updates. I'm very suspicious that something more than SMBv1 got turned off or changed, but it's quickly become obvious that this diagnosis is beyond my limited expertise.
Any suggestions will be greatly appreciated. I sure would like to get this going again before I'm called back to work.