Taskbar not reappearing after standby

[stephan54]

Usually the T60 starts up fine after standby, but regularly the windows screen comes back with the icons on it, but the task bar is missing. A control-alt-delete shows no programmes are executed and the poweroff option can be clicked but nothing happens.
So I have to hold the power off button till it switches off, restart and the problem is gone.
Does someone else have this problem and what could be the cause.
Thanks for your assistance
Stephan