Hi, @prostr,
The 503 error is a very general HTTP status code that means something has gone wrong on the web site’s server but the server could not be more specific on what the exact problem is. They are often caused by plugin or theme function conflicts, or by configuration issues from your hosting side.
First of all, make sure that your website uses PHP 5.3 or higher. PHP 5.3 is the minimum required by our plugin. You can check it on the Site Health section of WordPress. If it isn’t, please contact your hosting provider.
Now, you can try these options, in order:
– Update all plugins (make sure you have a backup of your site first!). There’s a chance you have a problematic plugin that will solve the issue by just updating it.
– Try deactivating all plugins and install ShortPixel. Does it work? If so, activate one by one the rest of plugins until you find the problematic one.
– Change the theme (you can switch to Twenty Nineteen, the default WordPress theme) and see if ShortPixel installs now. If it does, please contact the theme author, so they can solve this issue.
– If that does not resolve the issue, it’s possible that a .htaccess rule could be the source of the problem. To check for this, access your server via FTP, or a file manager in your hosting account’s control panel, and rename the .htaccess file to whatever you like (don’t delete, just rename it so you can restore it if needed). If you can’t find a .htaccess file, make sure that you have set your FTP client to view invisible files.
If that doesn’t help, we’d suggest to contact your hosting provider. They may be able to see more error messages or have a better understanding about the error.
Best,
