windows 7 - problem sending command to the program...

I windows 7 - 64 - problem sending command to the program...whenever I click on a file in explorer i get this problem...often after a few sec it does open the file..is this a time out thing..how can I stop it..not just a new even but irritating

Your HDD may be busy with a background task at the time you're clicking a file. Defragmenting could help a little.