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The Batch Upgrade processes the project files one at a time, saving them to new files. If a project has already been upgraded then the file will be skipped. If there is an error upgrading the project then you will be alerted via a dialog box and instructed to perform the upgrade manually (ie. open the file in the IDE and save it). Please note that the The upgrade process will not modify or delete any of your old project files (including their auxiliary files).
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