Do not update to version 3.9 (possibly even higher).
The WordPress plugin "BackuUpWordPress" leads to a fatal error after updating to the latest version 3.9 (probably also 3.10). Sometimes the backup files on the server are deleted. Occasionally the infamous "white screen of death" appears with the message "The site is experiencing technical difficulties. The website is offline and logging in to the backend is no longer possible. It is best to deactivate the plugin, delete it from the plugin directory and use an alternative instead!
Alternatives BackUpWordPress
The original development team of BackUpWordPress gave up support and development last year. Presumably there were some handover issues. However, there are also reports that the plugin was hacked. However - there are good alternatives
- UpdraftPlus free of charge and very up-to-date
- Jetpack The core functions, including backup, are free. But Jetpack can do a lot more.
- Duplicator can also backup and has additional features regarding page migration.