A customer complained that a particular download could not be extracted. The files in question were updates for a game. He had no previous problem with files from that game maker. He called the game maker and was assured that the files were OK. That it must be his computer or the download. After trying the download again he called me.
When I investigated. I found that no Zipped files can be extracted. There is no "Extract All" selection when I right click any ZIP file. When I tried to reveal the file extensions and expose hidden files do I could see what I was doing, the command did not work. When I went back to the menu in "Organize Files" nothing had changed.
I also discovered that 7-zip - among other things - had somehow been installed on the computer. I uninstalled 7-zip and several other pieces of trashware, ran Malwarebytes, Superantispyware, Eset Online Scanner, and Tweaking.com Windows Repair.
This customer does not install anything but shrink-wrapped games on this particular computer. He does download updates, but he does not do multiplayer. And, if anything seems complicated, he calls me.
Short of a complete OS reinstall, which would be laborious given the number of games in this customer's inventory, what do I have to do to get this machine to function properly again.