I would uninstall 7zip and use Windows Compressed Folders to extract zipped files. Also, Compressed Folders are easy to use by adding all your content to want to email or upload to a standard folder, right click that folder and choose Compressed Folder. Now you have a legacy zip file which can be easily opened by a recipient.
If you are going with 7ip for encryption reasons, that's another story.
If you're determined to use 7zip then uninstall it, go to Organize on the Toolbar, choose Folder and Search Options, unhide (hidden files and folders). Then visually search Program Files (x86), Program Files, User Accounts (your account) AppData, Roaming/Local folders for any remnants of 7zip. Run CCleaner both cleaner and registry cleaner.
Reboot your system and run CCleaner again. After it's cleaned-up everything Reinstall 7zip. Make sure when you install 7zip.
Let us know how it turns out.