I think this is what you are looking for: Security Tab - > Lock File.
As I think someone else responded, the file does automatically lock on filing.
I haven’t done it, but you can set post print actions to include locking the file, (see top right for individual print). But if you want to set the default for a print set then File - >Options – T1/P1->Pint-> Year-> print Set-> edit [top right].
When you open a locked file, Taxcycle will have a banner just under the ribbon to indicate it is locked and one-click to release:
Gregory Marko PEng, MBA, CPA CMA
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