Hi
I am looking for some advise from anyone who has upgraded to 10.3. I attempted to do this today and have experienced a problem signing in afterwards. In the past when I have performed upgrades (just on my laptop) it has been a simple matter of uninstall old version, reinstall new version and everything works. This time however when I have installed 10.3 I am unable to sign in as before, i get the message below:-

My key file is unchanged and in the correct location, the admin account is still there. If I uninstall 10.3 and revert back to 10.1 then it all works fine as before and I can sign in.
Can anyone offer any tips on this?
Thanks