I have been helping my parents with setting up their new computer.

It had Windows 8 installed and I ran the Windows 8.1 update on it.

I worked with them to pin all of their favorites to the start page.

They called me and told me 3 of the tiles disappeared.

I then helped them to pin 1 of the 3 on the start page again.

We used the computer for an hour or so and then when they went back to the start page, the one we re-pinned was gone again.

Is this a known issue? Any permanent reliable fixes?