Error Message in Skype setup

Hello experts,
I am trying to set up Skype, but I get the following error message.
What causes this Error 1638 on Skype?

Skype – Information
Information
Installing Skype failed; code 1638
Another version of this product is already installed. Installation of this version cannot continue.
To configure or remove the existing version of this product, use Add/Remove Programs in Control Panel.
need a solution.
Please suggest to me.
Thanks
