Menu item "Pin this program to the taskbar" gone

Soon after installation I somehow managed to unpin the Libraries icon by mistake and now I can't get it back. I know how it's supposed to work (start explorer, right click icon, select pin to taskbar) but I can't do that because the pin option does not show up when I right click. Attached is a screenshot showing the situation. I'm using retail Windows 7 Pro.

One possible cause that I have found is related to registry changes to eliminate the shortcut arrow. I did experiment with that using WinBubbles 1.76 right before this happened, but I have the regular shortcut icon enabled now and the registry entry HKEY_CLASSES_ROOT\lnkfile\IsShortcut is present. Given the apparent complexity of the taskbar implementation, it wouldn't surprise me if this is what caused the problem, but I haven't found a solution yet. BTW, the pin option is present for other applications like SnagIt, regedit, etc.

Any more thoughts on how I can restore the right click option to "Pin this program to the taskbar." for use with explorer/libraries/documents?

Thanks.

Does this happen for all icons or just the one you diplayed in the screen sfot?

@richc46 - Good point. I do have several restore points around that time. I don't have a system backup image, but I guess I'll make one once I get this fixed!

@reghakr - Yes, every other program still has the "pin to taskbar" menu item. It is only missing on the explorer/libraries icon.

Open Windows Explore to the C:\Windows directory. Locate explorer.exe,. Drag it to the desktop and choose Create shortcut here. Try pinning that to the taskbar. If it works, you can choose Close Window on the non-working one.

@reghakr - Nope, that's the problem. The "pin to taskbar" menu item is gone for explorer, no matter how I start it running. See attached.

Even for rthe one that i suggested?

Yup, that's where the explorer.exe shortcut came from that is shown in the image.

Just for information, I to had upinned my library folder from the task bar and tryed everything I could think of, including everything mentioned in this thread, but the only way I was able to get it back was a repair install.