There are two sides to this, the technical and the commercial.
From a technical point of view, installing version 17 on a machine will normally replace the existing version 16. The user must then select a different folder for version 17, and then the two versions can co-exist without problem. (When installing a 64-bit version, like v17, in parallell to an existing 32-bit version, like 15.0, this is not an issue as they reside in different program folders.)
From a commercial point of view, Mapinfo as "Node-locked" is licensed to a "named user". Having two versions installed on the same machine (or "device") for the same named user is within the permitted usage.
The terms and conditions are outlined in the End User License Agreement (EULA).
Note - always check for the latest version as these terms are subject to change. The current EULA (Nov 2018) has a section 2b stipulating the Use Rights for Named Users: "
You may install and use Products on an individual Device [...] so long as the number of Devices [...] does not exceed the number of Named Users specified on the Order Form."------------------------------
Hakan Karlsson
Presales, Pitney Bowes Sweden
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