Aha! Norton seems to have updated itself recently. Several screens have changed slightly. In my ignorance of AV technology, I never considered this as a possible source of my problem. I agree that I probably could install Tk by turning off all AV. That would not help if AV later deletes the suspicious file again. I have found a page of options that looks promising. I still have to study them in view of your comments. Thanks.
Bill

In reply to Re^6: Tk::Canvas not working by BillKSmith
in thread Tk::Canvas not working by BillKSmith

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