i completed my client site in wordpress,i quickly submitted this website into client server(FTP) but site won't open this error is occur " Warning: fopen(piecemakerXML.xml) [function.fopen]: unsuccessful to spread out stream: Permission refused in F:inetpubvhostskni.com.myhttpdocswp-contentthemestwentytenheader.php online 133 can't open file"

It is a file system permissions problem. WordPress doesn't have permission to gain access to that file or even the folder it's in. You will need to change that. Most FTP programs possess a CHMOD command built-in, or spend to the server, or make use of the hosting user interface.

Look into the permissions from the file to make sure it is a minimum of readable through the owner. And when you should also email it, it ought to be writable

Browse the page using blogging platforms about file permissions. It features a very good listing of example permissions
http://codex.wordpress.org/Changing_File_Permissions

Also Take a look at wikipedia

And also to Change file permissions, do what @Serta stated in the answer.