On Friday (3/22) we observed a few FTP uploads failing. The failure's were logged as:

Caused by: java.io.IOException: Unable to determine system type - response: 530 Access denied.

On Friday, we were able to re run the uploads using the same credentials about five hours later, and the files uploaded successfully.

This morning and yesterday morning (3/24 and 3/25) we had more uploads fail with the same error. The error persisted on retry.

This is behavior we haven't observed uploading files to your servers via FTP. Is something at Box affecting recent FTP uploads?