Backup Failed with Code 83

Hello, trying to backup to an FTP server and I am getting the following at the end of my log. Removed IPs and file names for security purposes. Any ideas?

27.01.2017 09:43:26 Creating New Backup…
27.01.2017 09:43:26 Deduplication is disabled because selected destination doesn’t allow random reads
27.01.2017 09:43:26 Searching specified backup base
27.01.2017 09:43:33 Base backup not found in original location, performing advanced search… this might take a few minutes
27.01.2017 09:43:34 Parent base not found.
27.01.2017 09:43:36 Cannot find a backup base. Defaulting to full backup.
27.01.2017 09:43:37 Creating full backup “IP”
27.01.2017 09:43:39 Collecting information…
27.01.2017 09:43:39 This might take a few minutes depending of the number of files and folders…
27.01.2017 09:43:39 Total items found is 42. Total size is 34.4 MB
27.01.2017 09:43:39 Writing initial items information…
27.01.2017 09:43:39 Writing items content…
27.01.2017 09:43:39 Cannot process security because running under limited privileges… Assuming defaults…
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:39 Processing C:
27.01.2017 09:43:40 Processing C:
27.01.2017 09:43:40 Processing C:
27.01.2017 09:43:40 Processing C:
27.01.2017 09:43:49 Reconnecting to “IP”…
27.01.2017 09:43:51 Reconnected s
27.01.2017 09:44:14 Reconnected successfully. Resuming with backup file (null)
27.01.2017 09:44:14 An error occurred while writing data to backup!
27.01.2017 09:44:16 Error 83 occurred
27.01.2017 09:44:17 Backup failed with code 83 (Invalid file handle).