FileZilla Forums

I'm using FileZilla Pro on Mac OS 11.4 with M1 chip.

I've searched forums and tried the suggested fixes: Transfers FTP file types set to Binary. Deleting and reuploading. I'm not receiving any error during/after upload. File size matches the original. FIlename is 2021approvalformnewtoindustry.pdf.

Originally I was dragging from Finder into the remote site for upload. No issues uploading. When I got the failed message in Chrome, I downloaded the file to my desktop (which FZ has access to) and tried again. No change.

I sent the link to a colleague and they get the same error message on Chrome ("Error: Failed to load PDF document." with a Reload button). I've tried an Incognito window. I've tried another browser (Safari) and same message.

I've also tried the traditional FileZilla Client and same experience.

Not sure what's going on. Any suggestions on how to remedy this?

Digging deeper - I was able to upload a PDF successfully yesterday, but the file size was much smaller. Around 38,000 KB for yesterday's file vs. 150,000 KB with today's file.

Are you using integrity-protected, secure FTP over TLS, or are you using corruption-prone, insecure plain FTP?

Tim, I'm not sure. How do I check?

If you are connected securely in FileZilla, there is a little lock in the status bar, at the bottom-right.

I've attached what my FileZilla screen looks like. I don't see a lock in the bottom right.

I just noticed the message in the startup log at the top:

"Insecure server, it does not support FTP over TLS"

My coworkers are using the same program (either FIleZilla or FileZilla Pro) with the same server (remaxmi), two of them on Windows and one of them on Mac (non-M1 chip), and none of them have issues uploading.

Lack of FTP over TLS support is something the server administrator or server hosting provider needs to address.

With plain FTP, incomplete transfers can have any number of reasons. The most likely culprits are faulty firewalls and NAT routers.