Issue:
You want to migrate your custom AutoCAD settings from a previous version.
Solution:
To Migrate from a previous release
When you launch AutoCAD or one of the verticals for the first time after install, the Migrate Custom Settings utility should automatically open.
This will allow you migrate custom profiles, menus, tool palettes and other settings into the current version.
**Not all AutoCAD products have this option**
**The Migrate Custom Settings detects previous versions installed on the same machine**
NOTE: It is strongly recommended to NOT select the CUI to migrate, that copies the CUI from the older version and uses it in the newer version. That can cause instability and functions to not work. As an example, if you migrate the CUI from AutoCAD 2014, then some of the new functionality and commands may not work (like DWG Compare or PDF insert)
If you choose not to migrate, you can run the ‘Migrate From a Previous Release’ later on from the Start Menu.
You can also run the AdMigrator.exe from the product’s installation directory:
Eg. For AutoCAD 2021
If you need to migrate previous version settings from another machine, install the newer version on the old machine or older version on the new one. Then use the Export AutoCAD Settings and Import AutoCAD Settings shortcuts to transfer settings between the same versions and the ‘Migrate From Previous Release’ or vice-versa.
You can only export and import settings between the same version.
For more information on how to export and import settings:
https://knowledge.autodesk.com/support/autocad/troubleshooting/caas/sfdcarticles/sfdcarticles/How-to-import-and-export-backup-settings-to-and-from-AutoCAD.html
How to create export and import shortcuts in Map 3D and Civil 3D:
https://blogs.rand.com/support/2018/09/creation-of-import-export-civil-3d-or-map-3d-user-settings.html