If the import stalls and fails to respond after a few minutes; if you get a 404 message or similar error; you are experiencing PHP configuration limits by your hosting provider that are set too low to complete the process. The best solution is to contact your web host and ask them to increase those limits to a minimum, as defined below:
- max_execution_time 900
- memory_limit 128M
- post_max_size 128M
- upload_max_filesize 128M
Once these changes have been made, reattempt to import the demo content and let the process run until completion and you see the "All done." confirmation message.
If you are unable to modify the limits above or if your hosting provider is unhelpful, the workaround is to continue selecting the "Import" button until all demo content has been imported. Please note, you will likely see a long list of messages that say "Failed to import" or "Media already exists". This is just letting you know that those files have already been successfully imported. However, until you see the "All done. Have fun!" message, your demo content has not been completely imported.
If you have to attempt the import several times, it's possible you may have duplicate menu items added to your Primary Menu. Simply go to Appearance > Menus and delete the duplicates, as needed. Of course, if you don't need the demo menu, simply build a new one and set it as the Primary.
If all else fails and you are unable to replicate the demo, click the "new support ticket" link above and include temporary admin credentials to your site and we'll be happy to take a look!