Installing via ZIP is one screen and two clicks. What trips people up isn’t the procedure: it’s three details that show up in the same spots every time. They’re marked along the path below.
Plugin
- In the WordPress dashboard, go to Plugins > Add New.
- Click Upload Plugin, at the top.
- Choose the ZIP and click Install Now.
- Click Activate Plugin.
Theme
- Go to Appearance > Themes.
- Click Add New and then Upload Theme.
- Choose the ZIP and click Install Now.
- If the package includes a child theme (
-child.zip), install both and activate the child.
Detail 1: the right ZIP isn’t the one you downloaded
This is where most installs fail. The downloaded file is usually the author’s full package, with documentation and license inside; the installable is a smaller ZIP nested inside it. If you got the package could not be installed or stylesheet is missing, that’s it, and each one has its own article: for plugins and for themes.
Detail 2: the server may reject the size
A theme with a bundled demo easily goes over 50 MB, and a lot of hosting ships WordPress with an 8 MB upload limit. The screen disappears, comes back blank, or complains about the size. The fix is in WordPress upload limit, and uploading via FTP solves it without depending on any configuration.
Detail 3: updating is the same screen, with one extra step
If the item is already installed and you upload the ZIP of a newer version, WordPress shows a table comparing the two and asks if you want to replace it. That’s true from version 5.5 onward; on an older site, it just says the destination already exists. In both cases, and whenever the replacement fails partway through, the fix is in how to update manually. It’s worth backing up first, always.
After installing
Some items show a warning asking for a license key as soon as they’re activated. In most cases this doesn’t block usage and doesn’t mean something went wrong: the five scenarios are described in My license won’t activate.
