Try this one,
Repair the Taskbar
If your taskbar has disappeared from the desktop or
becomes hidden when you move your cursor near, it may be
due to a corrupt registry key.
Press
Ctrl + Alt + Del
Taskmanager would come up
click on file -> select new task -> type Regedit. **
go to
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion
\Explorer\
Delete the entire "StuckRects" key, or "StuckRects2" and
Close registry editor, restart the computer.
When Windows restarts the taskbar should be set back to a
default working state.
** Remeber to backup your Registry, before you continue.
