Windows shares keep dropping from OS X
I have similar problems with users on my network using Mavericks, where no such issue existed with Mountain Lion. Most users can live with it, and they simply re-mount the disk. Apparently, the SMB implementation on Mavericks is different than it was in prior OS releases. What I have found is that if I connect to drives using cifs://servername rather than smb://servername, this pretty much mitigates the issue. This has been true for NAS, MFDs with Windows shares, and Windows servers alike.