The connection was closed unexpectedly.
WHAT IT MEANS
The other end terminated the connection mid-transfer.
COMMON CONTEXTS
A large file upload interrupted A long-running request terminated A network interruption between you and the server A security rule closing the connection
DURING AN UPLOAD
Usually a size or time limit. Raise upload_max_filesize, post_max_size and max_execution_time in cPanel.
For very large files, upload a compressed archive and extract on the server, which transfers one file rather than thousands.
DURING FTP
Try passive mode. Try a smaller number of simultaneous connections in your client's settings.
DURING A LONG OPERATION
An import, an export or a backup may exceed limits and be terminated.
Use the command line where available, which has no execution time limit.
IF IT IS INTERMITTENT
Frequently your own connection rather than the server. Test on another network.
IF IT IS CONSISTENT ON ONE OPERATION
That operation is hitting a limit. Identify which limit and either raise it or split the work.
