I've followed the tutorial
https://www.mobileread.com/forums/sh...d.php?t=251201 to setup a Windows Visual Studio Environment to check what is wrong.
I've created a new network drive and I do some tests.
Calibre works on my network drive if I mount it on a root share folder (es. net use X: \\ip-address\folder). If I use Calibre inside a subfolders and I mount it as a network drive it fails (es. net use X: \\ip-address\root-folder\sub-dir).
I don't understand why.