I was just writing a very frustrated letter to a company because each and every zip folder from them were rejected by Windows 7 as being not-valid, when a bell started ringing in the back of my head. I aborted the angry letter, right-clicked some of the zip containers, clicked "7-Zip... Unpack to "...", and
voila! the zipped containers were all just fine.
So, my (64-bit) Windows 7 (Home Premium)
unzipper has broken down, and I have absolutely no idea what to do to repair it. The file association is still okay; "Open in Explorer". I have never used Windows to
create a zip container, but I use it every day to unpack single containers. If I have more containers, I always use 7-Zip, but for a single container, I always use Explorer.
Any suggestions on what to do (to repair it), please?