Saving e-mail details: puzzling behaviour of ATI Home 2010

Here's something odd.
Two copies of ATI Home 2010, both Build 6,053, installed on two computers running Windows XP, SP3.
On Computer A, each time I create a new backup task, I find that the form to give details of e-mail notifications is blank, awaiting my input.
On Computer B, each time I create a new backup task, I find that the e-mail notification form is already filled in - ATI Home has remembered my settings.
Curiouser still: I uninstalled and then reinstalled ATI Home 2010 on Computer B (to get rid of annoying and useless Nonstop Backups - that's another story!) and found that the reinstalled ATI 2010 still remembered my e-mail settings (so uninstall had not cleaned that little archive out).
E-mail notification works on both machines, btw.
Since you asked: Computer A's XP is Home; B's is Pro. ATI on Computer A is an upgrade from 2009; on B it's a fresh installation. Could either of those facts explain this odd difference in behaviour?