I seem to remember having to force Windows Vista to use NTLM v2 many moons ago to make it work with Samba. You might want to google for Vista +Samba +NTLM, and see if that does it for you.
Chances are, your old employer's infrastructure may have had some legacy systems that they had to force compatibility with, whereas your new system image doesn't have that "'baggage".
It's not likely to be a Samba issue, because I'm running Samba with Vista (laptop) and a Windows Home Server 2011 VM (based on Server 2008r2) at home, with no issues for years now. I do remember setting a couple of parameters in my smb.conf file, so I'll look those up later when I'm home to see what I'd set.
HTH!
/Mike