Too many parameters error

[mql_tester_01]

Why does trying to create this simple file write handle bring up error 5039?

         ResetLastError();
         int _h=FileOpen(_file,FILE_WRITE|FILE_TXT|FILE_COMMON);
         
            if(_h!=INVALID_HANDLE)
            {
               FileWriteString(_h,DoubleToString(m_account.Equity()-m_testing_deposit));
               FileClose(_h);
            }
            else
            {
               printf(__FUNCSIG__+" failed to create write handle: "+IntegerToString(GetLastError()));
            }

This code runs within a function in the ExpertSignal Class, part of the wizard classes.

[William Roeder]

printf(__FUNCSIG__+" failed to create write handle: "+IntegerToString(GetLastError()));

The call requires A) format string, B) one or more parameters. You passed no parameters.

printf("%s failed to create write handle: %d", __FUNCSIG__, _LastError);