How to Cut(Move) File from one Folder and paste to another folder

Hello Guys,
I am trying to move(Cut) one file from one folder and tranfer to another folder using System.IO.
Here is My Code
FileInfo fiThumb = new FileInfo(tPhysicalPath);
if (fiThumb.Exists)
{
File.Move(tPhysicalPath, strNewPhysicalPath);
}

I am getting Error while Doing this  - Cannot create a file when that file already exists.

Please give me Suggestion how to move files .Help needed Urgently !!
Thanks.

 
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