Due to different reasons we are forced to deploy two different putty executables on the same system, whose version might be out of sync. As both executables seem to store their settings in the same windows registry path, the concern arose, that the newer of the two versions might write settings in a different schema, that the older version can no longer process. This could in the worst case even lead to the older version being no longer able to start.

Is anyone aware if something like this happened in the past? How backwards compatible are changes in the settings schema in general?

I tried a search in the putty documentation, but couldn’t find anything regarding this issue.