Setting up an FTP server for Shareboxed

Shareboxed uploads straight to an FTP server: a NAS, the space that came with your hosting, a box someone in IT keeps running. Files keep their own names in a folder you can browse with any FTP client.

Field	Value
Server	the host, without a scheme
Security	which TLS the server speaks, see below
Port	leave empty for 21 (990 for TLS on its own port)
Username + Password	an account that may write
Folder	optional, a directory to write inside

1. Pick the right kind of TLS

Setting	What it means	Usual port
TLS	The connection starts plain and is upgraded before the password.	21
TLS on its own port	Encrypted from the first byte. Still common on NAS boxes.	990
None	No encryption at all.	21

Try TLS first; if the test fails on the endpoint, try TLS on its own port. Pick None only for a server on your own network: the password and every byte travel readable.

2. Find the account details

A hosting account (cPanel, DirectAdmin, Plesk): the FTP accounts page. Make a separate account for Shareboxed and point its home directory at the upload folder.
A NAS (Synology, QNAP, Unraid): enable the FTP service, make a user with write access to one shared folder. Synology's FTPS (explicit) is the TLS setting here.
A server you run: any user that can write to the directory. vsftpd and pure-ftpd both do explicit TLS with a Let's Encrypt certificate.

3. Open the passive port range

Uploads use passive mode: the server names a second port and Shareboxed connects to it. A server behind its own firewall needs that range open and has to advertise its public address (pasv_min_port/pasv_max_port on vsftpd, Passive port range on a NAS). Without it the login succeeds and every transfer hangs.

No shareable links

The Sharing switch is not offered for FTP. A download link works because one request for one file can be signed without handing out the account. FTP has nothing to sign with. Point recipients at whatever already serves the directory over HTTP, or use an S3 or R2 connection for batches that need a link.

When something does not work

Press Test Connection first. What it can say:

Test Connection says	Fix
Missing credentials	The Username or Password field is empty or was not saved.
Invalid endpoint	Typo in the server, or the wrong kind of TLS: try the other TLS setting, and check the certificate.
Invalid credentials	The server refused this username and password.
Insufficient permissions	The folder does not exist, or this account cannot enter it.
Not reachable	Nothing answered on that host and port: a typo, a firewall, or a server that only resolves on another network.

One more that only shows up later:

Test passes, uploads hang at 0%: the passive port range is closed, or the server advertises a private address. Step 3 above; this is a server setting, not something a client can work around.