Mac: Opening 2.4.2 audacity file in 2.3.3

Working on a long distance project. I want to set up an audacity file for my collaborator in 2.4.2, email it to them so they can open it in their 2.3.3 version. This is a fairly simple project. I will provide a backing track to which they will add a few tracks. Will the version difference present any problems? I could have them update to 2.4.2 of course. Also I need to verify my friend uses a Mac. If he’s on Windows, does the computer difference or version difference present a problem?

My other alternative is to download version 2.3.3 onto my computer to set up the file for him. Can I have two different versions of Audacity on my one Mac Imac Version Sierra 10.12.6?

The current version of Audacity is 3.0.4.
Projects created in Audacity 3.x are NOT compatible with Audacity 2.x

Since you know that Audacity 2.x works for both of you, I’d suggest that you both use Audacity 2.4.2 (You can get it here:

Probably not, but be careful when naming files. Windows does not allow some “special” character to be used in file names.
If you stick with letters “a to z”, and numbers “0 to 9”, and space, and underscore “_” then there shouldn’t be any problems.
Do NOT use the backslash character "" in file names as that character will definitely cause problems on Windows.

Note that projects in Audacity 2.x have a project file “projectname.aup” and a data folder “projectname_data”.
To send an Audacity 2.x project, the easiest way is to make a ZIP archive containing the AUP file and the _data folder. The recipient will then need to “unzip” (extract) the contents of the ZIP file onto their computer.

If you both update to the current Audacity 3.0.4, then sending files is easier because an Audacity 3.x project is a single .AUP3 file.

Note that Audacity projects are often very large. You may find it convenient to use dropbox or similar to exchange projects, but do NOT work on projects that are on a “cloud drive”. If you use a cloud drive (such as “One Drive” or “Google Drive”, or “iCloud”), then move the project to a normal folder on your computer’s local hard drive before opening it in Audacity.

Thanks for the replies. Not ready to update to 3.04 yet since I also have a second computer I used which is very old and wouldn’t accept the latest version and I need to use one version that works for both my computers. (Also some reported concerns about the new privacy agreement for version 3, which I won’t go into here.) Good tip on naming files. Bottom line is that since the new recording will be going in only one direction–from him to me–he can easily send me individually exported wav files for the few tracks he’s doing and I’ll then be able to import these tracks into Pro Tools and line them up. I’ll make sure he updates to 2.4.2.