Installation Error

I want to purchase windowblinds but I thought I would install Stardock Central first. When setup gets to about 99% it gives me an error that says "Explorer.exe is not a valid win32 application." When I click "ok" it then says "Could not execute the external program explorer.exe" When I click Start->Run then type in "explorer" it gives me the same error.

I've never had this happen to me before with any installation. I would like to solve this so I can feel confident to buy Windowblinds.

Thanks in advance.