Hi,
I need your opinion. Time to time when uploading photos an error occurs in media library: »Failed to write to disk«. After i clear cache i can upload photos again so i thought there was a problem with the plugin (wp-optimize) so i uninstalled it and install WP Super Cache (simple configuration).. same problem but after clear cache with super cache i still cant upload media. In the meantime, a new wordpress 5.6 upgrade came, so I wanted to upgrade it, but an error also appears here: Download failed.: The checksum of the file (d41d8cd98f00b204e9800998ecf8427e) does not match the expected checksum value (a9c1d9d8ec9af77e009c61561fedbf0b). Also i cant install new plugins (Installation failed: Could not copy file.).. After i uninstall WP Super Cache im able to upload media..
I called the hosting where they claim there is no problem with them. In control panel looks OK with disk space (they are using ISPConfig panel).
How to diagnose the problem?