Hi John,

I ran into this last fall. One of our customers just replaced their machines with Windows 10 and IT had changed some of their network configurations. What we started seeing were "unable to read file" errors throughout the day - this on a Tax collection package that had been running on the 2008 server from the day it was installed, 4+ years ago.

We initially suspected SMB2 issues and ran the Alaska Software smb2-infocache.msi on each machine, but that didn't do much of anything. I started googling the error and ended up searching for read errors on mapped drives. I eventually stumbled across the link I had reference before, which mentioned Windows 10 losing mapped drives. (https://community.spiceworks.com/topic/1139165-windows-10-losing-mapped-drives?page=2). here's the best answer from that link:

"After putting up with this for months, I've found a solution. It appears this issue has actually been around since Windows 8 and is caused by Group Policy drives which are set to "Recreate". Windows 8/10 automatically runs Group Policy updates in the background and disconnects/reconnects the drive to Recreate it.
Change the drive to "Update" in group policy and the issue will disappear!"

After passing that information along to the IT guys, the file read/write errors stopped completely and they haven't had a single error since.