Hi Desktop. Welcome back.
According to this post, you found the answer elsewhere, but don't say where or what the answer was:
Programs sometimes don't open?
It's always good to go back to the forum wherever you posted the question to update the thread with whatever solution you may have found.
At any rate, have you tried this?:
Programs won't open from Windows taskbar
Also, here is a google search on the matter:
Windows 7 Programs Don't Open From Taskbar - Google Search
Post back and let us know if your problem is not resolved. If this
does resolve your problem, please post back to let su know what worked. It helps others who might be searching for the same answer.
James