My FTP/SFTP credentials are not working – what shall I do?

1. Read the error message, and try Google

Our experience is that often people are simply afraid of error messages – and often the reason is staring them in the face. Don’t be put off by an error message; read it, and if you can’t guess what it is telling you, then try Googling it. There are very few problems in the world of WordPress that nobody has had before.

2. Double-check you have the right credentials

Firstly, the obvious one: have you tried the credentials in another FTP program, to check that they are correct? If not, then this is the first thing to check. In this case, you are likely to be getting an error about wrong credentials.

3. Double-check you entered those credentials correctly

Secondly, another obvious one: double-check you have entered the credentials correctly in UpdraftPlus. For the FTP server name (a.k.a. host name), it should simply be a host name with nothing added, e.g. “ftp.example.com”.

4. Does your FTP server require encryption, and you’re not using Premium?

Thirdly, perhaps your FTP server requires encryption, but you are using the free version of UpdraftPlus? If your FTP server requires an encrypted connection (i.e. forbids non-encrypted connections), then you will need to use UpdraftPlus Premium, which includes this. The same holds if you are using SFTP (which is actually a different protocol than FTP, despite the similar name).

5. Is the FTP server deliberately blocking your webserver’s IP address?

Fourthly, is it possible that the FTP/SFTP server has an access control list, which limits logins to certain IP addresses only? You’d be likely to know about this – but we all forget from time to time! Similarly, is it possible that your FTP server blocks login attempts after you’ve got the password wrong too many times? Or possibly, it has limits on how many users can login at once – and those limits have been temporarily reached?

6. Mis-configured FTP server / firewall

If you are seeing the error message php_connect_nonb() failed: Operation now in progress (115) as part of the message shown, then you can be forgiven for finding that a rather cryptic message (from PHP’s FTP engine).

The meaning/cause of this message is your FTP server is misconfigured. Part of the FTP protocol involves the FTP server telling the FTP client its own IP address. This can break if your FTP server is behind a particular type of firewall (known as a NAT firewall). The NAT firewall is meant to re-write the FTP traffic to change the indicated address; or, the FTP server needs to be re-configured to indicate the external address. You can read some of the technical details about this setup, here.

How to fix it, in this case? If you are using UpdraftPlus Premium, then by default FTP is encrypted. It may be that if you switch to non-encrypted FTP, then the problem will be resolved. (This happens if the NAT firewall is meant to be doing re-writing, but the encryption prevents it from doing so). To do this, go into the ‘Expert’ settings (at the bottom of the UpdraftPlus settings page) and turn off SSL (encryption), then you get better success (test first – and if it works, then remember to save your settings).

If non-encrypted FTP also does not work for you, then the fault is on the FTP server, and you will need to contact the FTP server administrator to ask them to resolve the issue.

Sometimes the question arises – “Why does this work for me in (some FTP program, e.g. Filezilla), but not in UpdraftPlus?” There are two reasons for this: 1) the FTP program (e.g. Filezilla) may not be running from the same network as UpdraftPlus is on (e.g. the FTP program is on your PC, whereas UpdraftPlus is on a webserver at a hosting company, so they are facing different firewalls on route to the FTP server). 2) Some FTP programs (including Filezilla) have a work-around in them to detect this situation, and guess what the FTP server meant to say, instead of responding to what it actually did say. PHP’s FTP engine (which PHP applications, like WordPress/UpdraftPlus get to use) in older versions does not have this (there’s an open request in PHP’s issue tracker for it to be added). A version of this feature was added to PHP in version 5.6.18 and 7.0.2 – so, if you update your PHP install to those versions, you might then have success.

7. Other firewalling issues

Sixthly (and, most cases of this problem are this one), if you have got this far, then your problem will almost certainly be with firewalling on outgoing traffic from the webserver. i.e. The webserver is configured to only allow outgoing traffic that the server owner (i.e. the web hosting company, usually) has specifically configured to allow. In this case, you will need to ask for support from the people whose server it is.

One variation on this problem (firewalling) is that the firewall is theoretically open, but partially broken. You may find that if you go into the ‘Expert’ settings (at the bottom of the UpdraftPlus settings page) and turn off SSL (encryption), then you get better success. (This suggestion does not apply to the free version of UpdraftPlus, which does not support encrypted FTP at all; and does not apply to SFTP, as that is always encrypted).

Another variation on this problem is simply that some ultra-low cost web hosting companies disallow websites to use FTP entirely… because their business model is based on making sure you use very small amounts of resources… and backups that want to copy your entire site don’t fit into this model. If you suspect your web host might be of this kind, then it’s also worth confirming that with them.

One obvious pointer to a firewalling issue (though this need not always happen) is that there’s a significant delay before the error message is given. This indicates that the network traffic is simply being dropped. (Some firewalls immediately send back “that traffic didn’t get through!” replies, but others do not, and a timeout eventually occurs).