ZIP file opens with WinZIP and windows reacts

I was having the same problem with file associations constantly changing (sometimes it seemed almost hourly).
Based on what other members were saying about WinZip I ran a few tests.
Sure enough, every time I opened a WinZip file it caused some file associations to change back to Microsofts defaults.
I was using WinZip v16.5 at the time.
I upgraded to WinZip 20 and have never had a problem with changing file associations since that day.

Windows 10 - An app default was reset (older WinZip versions) [Winzip support KB article 401]

I wish many of those Winzip users have looked at that Winzip KB support article before upgrading to Windows 10. It turned out to be a compatibility problem between old versions of Winzip & Win10.

Nevertheless, upgrading to either Winzip v19.5 or v20 solved the problem as I too encountered problems using Winzip 16.5 under Windows 10.