I am using adobe acrobat reader 6 which is a very heavy on my old pc, I still have 5.1 source on my system but I need an advice before uninstalling ver. 6 and install ver. 5 ... Does ver. 5 has all (at least most of) the features ver.6 ? Will be some times when I open a file and then receive an error messages that some feature are not supported by this version? thanx in advance..