I tried to find the link in the Friends and Family area but there was no link to switch, only to add a family member or a non-family member.

I had a look in Windows Store and I was still logged in...

Sorry yes, the only account on the computer is my account as a local account that was an MS account

I followed the steps that were in the original reply.

Change my account to local
Change to MS account using wifes credentials

Thank you for the reply.

Unfortunately its not quite as easy as that...

I have changed my account to a local one

I then have tried changing it using her details as a microsoft account, the...

My wife has upgraded to Windows 10 and was using her login details with no problem.

When she needed to install a HP Printer Driver, a Microsoft Account was asked for. She couldn't remember her...