Anybody know of a Mac-happy SFTP app?

You will find numerous FTP utilities at MacUpdate. OS X has built-in FTP support for the Finder, but it only can download files. Use Connect to Server under the Finder's Go menu.

Transmit is nice (for a fee).

Cyberduck if you need free.

http://www.panic.com/transmit/

https://cyberduck.io/

Alternative options can be seen at …

http://alternativeto.net/software/transmit/?platform=mac

I'm not sure I trust Macupdate.com (or alternativeto.net for that matter 🙂), head over to the developers site for downloads, the aggregation sites have a habit of bundling junk with the installers.

developer.apple.com.

I've used MacUpdate for decades, and I've never had an issue with downloads. Anyone who tells you otherwise simply doesn't know of what they speak.

I linked to the developers sites. For the 'download aggregator' sites you need to follow the link to the developer site, but they are often tough to find. Cnet's downloads site has been bundling adware with certain software downloads, I don't trust other sites for that reason. Macupdate is probably safer than other sites but I can't see any point risking it.

Cyberduck has the free version above the Mac App store version link.

They explain why you should donate to register at…

https://cyberduck.io/donate/

but the app is free.

I'm referring to the third party developer site, not developer.apple.com.

Download aggregators have been bundling adware with genuine Mac software installers - it's best to avoid them all IMO.

CNET was doing that, but have stopped, mostly. That has never been done at MacUpdate.com. They have always been safe.

You'll need to be more specific - what app did you get?

Are there any error dialogs? Are you sure you are using the correct credentials for the server?

Finder uses the 'Go menu > Connect to Server' to open ftp connections. Enter FTP://server-name.com for the URL then you should be prompted for any required login credentials.

If this is for a web service consult any setup guides on that service, they usually cover common mistakes (like different port numbers).

For a while Cyberduck was the best open source FTP client for Mac, but now that FileZilla's ported over, I prefer that (and, yes, it supports SFTP).

You can try another ftp server just to see that you have a working internet connection…

See if you can view ftp.mozilla.org/pub/mozilla.org/ in Cyberduck

Or ftp://ftp.mozilla.org/pub/mozilla.org/ in Finder

It is possible for network administrators to block ftp connections (normally inbound traffic for security reasons) that does not apply to residential connections, you would need to check with an administrator for more info on that if on a corporate/ education site etc. Does the server have any guidance for the settings? It may be behind a firewall that only allows local access (sorry it is not clear if you are accessing a server that is public or not).

Toggle the log drawer in Cyberduck to see more detail as the connection initiates, it is in the View menu. Post it here if you want help with that (check it for any personal details & redact them).