Dear Users, I already download & installed ActivePerl 5.6 & rrdtool-1.0.33.x86distr.zip. Also changed directory to c:\rrdtool\perl-shared & finally applied command ppm install rrds.ppd But it will give error of "Failed to load PPM_DAT file Can't use an undefined value as a SCALAR reference at C:/perl/site/lib/PPM.pm line 1678, <DATA> line 40." Can you help me in this matter ? Waiting for your positive reply. Regards, Ankur