I experienced the same odd behavior but resolved it.
Troubleshooting another issue, I deactivated all plugins. After reactivation (all), Gallery was missing at the left hand side. I deactivated it again and went out of the browser. Starting again, activation resulted in Gallery showing up.
Hello @mrzpro,
We should probably check for an existing conflict
Let’s check if it is an existing conflict:
– Temporarily deactivate all your plugins except NextGen Gallery.
– Is the problem solved? Then, it was caused by one of your plugins. Please check one by one and find the one causing the problem.
– If the problem is not solved with the deactivation of the plugins, try changing to a standard WordPress theme, it could be a conflict with your current theme.
You can also try to manually upload the plugin.
https://www.imagely.com/docs/installing-and-updating-nextgen-gallery/
Please, let us know if that works for you.
We are happy to help!
