@PA_Fan:
Thanks.
I had a subsequent problem where the skin somehow became corrupt, with all buttons hidden, and thus rendering PA inaccessible.
For various reasons, I updated to16.00.69 by downloading the entire file, so was able to use this to repair the installation.
When that was complete, PA was restored to normal look (albeit with settings lost) and the delete/refresh problem has been cleared/fixed.
when something like that happens next time, try to save the registry so we can reproduce it here. Same goes for the repair, manually deleting HKCU\Software\PowerArchiverint would have likely reset it all back without need to repair.
thanks!