Different IDE versions on one PC

Sure it is possible to use different versions in zip format. But there is just one settings file for the IDE and that means i have to put all the libraries in the IDE folder alongside the libraries that came with the IDE.

Is there another solution?

If you want to have a different preferences file for each version then create a folder named portable inside each Arduino IDE installation folder. The next time you start the IDE a new preferences.txt file will be created inside that folder and then you can set the sketchbook location in File > Preferences. There are some limitations to the location of the sketchbook folder in IDE versions previous to 1.6.7 see Sketchbook location on Portable Edition · Issue #4103 · arduino/Arduino · GitHub

MrGlasspoole: Is there another solution?

These days with virtualization, there is probably no need to have one PC. You can have as many PC's as you want. I installed Oracle VirtualBox, and I can spin up as many Linux boxes as I want. My favorite is CentOS 6 because it is just like the Red Hat I use on many servers at work (or I suppose you could say it is Red Hat). Oracle Linux is also good. I am not wild about Ubuntu and its derivatives, but I realize it is very popular.

@pert, thanks. But then there is still a problem. I only have my sketches in one IDE. It would be better there was a path setting only for "libraries" and "hardware".

@dmjlambert, sure. I have a Hyper-V Core server running Debian, pfSense, 1x Windows and FreeSwitch. I also have VMware on my Workstation... But running a whole VM just for one different Arduino IDE?

Buy the way i'm also not a Ubuntu guy. I'm a Debian without GUI guy :-)

MrGlasspoole: I only have my sketches in one IDE.

So you want different {sketchbook}/libraries and {sketchbook}/hardware location for each IDE versions but you want the same sketches to show up in File > Sketchbook for all the versions right? I've never used them but could you create a symlink in the sketchbook folder of each IDE version to the folder where you have your sketches? I suppose that would mean you'd need to do something like File > Sketchbook > sketches where sketches is the linked folder but that's not so bad. With Arduino IDE 1.6.6+ you might not be able to use Windows directory junction but should work with symbolic links in other OS see: https://github.com/arduino/arduino-builder/issues/90