Schema of a sharepoint

I am very new to sharepoint.
Writing code for batch update.
I am getting an error "Can not complete Action."

string methodFormat = "<Method ID=\"{0}\">" +
"<SetList>{1}</SetList>" +
"<SetVar Name=\"Cmd\">Save</SetVar>" +
"<SetVar Name=\"ID\">{2}</SetVar>" +
"<SetVar Name=\"urn:schemas-microsoft-com:office:office#Status\">{3}</SetVar>" +
"<SetVar Name=\"urn:schemas-microsoft-com:office:office#Modified_x0020_By\">{4}</SetVar>" +
"</Method>";

Please suggest me, whether i have to change schema name here urn:schemas-microsoft-com:office:office ? or keep it same...

Thanks,
Rajni Shekhar