Windows 7 - the task bar "folder" pinned "program"

I usually use it by pinning my frequently use folder,

so when I right click, the list of "pinned program (folder)" will be listed out, easy for me to access them in a click.

and one day, all the pinned programs gone.

so I attempted to "repin" all vanish folders, but even if I click to pin them, they just wont show up in the "pinned program" list.

the worst part, I right clicked, the only option is UNPIN THIS PROGRAM FROM TASK BAR where that program was not pinned in the first place (didnt show up in pinned list) , how come only this option pop out?

please help , thanks.

Can you pin anything to the start/taskbar?

Do a System restore.

If it quit working lets say yesterday. Then choose a restore point the day before that.

Try this first. Then we can go form there.
Just in case a tutorial for System Restore.
System Restore

Mike