• You have to save from AC18 to AC17 then open in AC17 and save down to AC16. You will/might lose information along the way, for example BIM Materials are not supported on 16 so that information will be lost going backwards. By the same reason you cannot work on the same file using different versions.
• The only good news is that if you have a license key for 18 it will work with 16 so you will need to get the installer for 16.
Eduardo Rolón AIA NCARB
AC27 US/INT -> AC08Macbook Pro M1 Max 64GB ram, OS X 10.XX latest
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