Using Old and New Versions of Max on the Same Machine
As you make the transition to Max from an older version, you may wish to run old and new versions side-by-side or at least keep them both installed at the same time. Here are some hints to make this easier.
Don't Overlap Your Search Paths
By default, when you install Max, everything except your preferences will go into a single self-contained folder. Nothing from your previous Max version will interfere with the installation of any previous version of Max.
Preferences Won't Overlap
As explained here, Max does not share preferences with older versions. Preferences files from older versions are not compatible. Do not attempt to copy them. Use the Max environment to create new preferences.
With comparable scheduler settings, Max has a slightly higher CPU utilization doing nothing than earlier versions do. So if you are trying to gain a bit more CPU while using Max, you may wish to quit earlier versions temporarily.
Virtual MIDI Ports (Mac only)
One confusing issue that arises when trying to run Max at the same time as an older version of Max is that the virtual MIDI ports created by the Mac version called "to Max 1" and "from Max 1" appear to be doubled. Due to the fact that old patches may store references to these virtual ports by name, it was not possible to give them new names to distinguish them from the ports in earlier versions. Furthermore, you will be confused because one of the ports with the same name will do the opposite of what you expect (it will be output when you expect it to be an input). To help eliminate the confusion, the virtual ports of other applications are shown in italics in the Max MIDI Setup window.