Subprocess Connection Error

On Windows, when I try to open IDLE, “IDLE’s subprocess didn’t make the connection.” message in dialogue is shown and IDLE is not opened.
What could be the solution?

Did you try reading the link that is shown in the dialog box?

There are several suggestions there for what the problem might be. Please try to check if they apply to you; in most cases the solution should be obvious. If not, please let us know what you discovered.

Thanks for your suggestion, but now I’ve reinstalled Python in my system and it’s working well.
If I counter same problem later, I’ll must let you know.