how to use fir1 for highpass filter with window

i have a problem while using fir1 with highpass and window function .

ex.

         fc=input('cutoff frequency   : ');
         fs=input('sampling frequency : ');
         order=input('order              : ');
         [b,a] = fir1(order,(2*fc)/fs,'high',rectwin(order+1));

but when i use '(order+2)' , there is no problem.

         fc=input('cutoff frequency   : ');
         fs=input('sampling frequency : ');
         order=input('order              : ');
         [b,a] = fir1(order,(2*fc)/fs,'high',rectwin(order+2)); 

the key point :: i want to use order = 5 and i want the result of 5 filter coefficients .