New
#11
Kevin, it turns out that the "old password" refers to your Windows user password, not a Microsoft account password. In an effort to get people to create/use Microsoft accounts, Microsoft wants you to abandon logging into Windows with your Windows username and password, and instead use your Microsoft account username and password. Thus, if you're still using your Windows username and password to log into Windows, you'll have to enter this as the "old password" when enabling Cortana. The reason they call it the "old password" (while not telling you which password!) is that in addition to enabling Cortana, it will secretly in the background change your Windows logon to require your Microsoft account info instead of your "old" logon info.
Once I got through this, Cortana worked. I tried it out for a couple of hours, found it worthless, and completely removed it from my system (which is also not straightforward; there's another thread devoted to that).