HowTo:Upgrade to a new version of ACIS or InterOp
When upgrading to a new ACIS or InterOp release, the new release must be installed in an empty directory, rather than in the same directory as the previous release. This applies to major versions, Service Packs, and Hot Fixes. Additionally, because they are installed in completely separate directories, multiple versions of ACIS and InterOp can be installed on the same system.
Note: This refers to version upgrades, such as moving from R19 to R20, R20GA to R20SP1, or R20SP1 to R20SP1HFx.
Because the new version resides in a new location, any environment variables that relate to the location of the installation (such as A3DT) will need to be modified. In addition, if you are upgrading to a new major version, a new license file will be required for Microsoft Windows platforms.