My question is this. What is the difference between the 7-zip rar files and when I use the compressed (zipped) folder selection on a file? What's the rar files for?
I rarely send zipped files. I used to have WinZip on my old computer. My generic office PC tower computer has XP Pro, SP3, Office 2003. (By the way, awhile back I upgraded to Office 2007 but found it totally lame and went back to 2003). A few reciepents of some PDF architectural building plan files say they cannot open my files when I send them with 7-zip. These are sometimes 30-60 page pdf building plans.