WARNING: XML ERROR (1): internal error: Huge input lookup

I am getting this error and a secondary error:
WARNING: XML ERROR (5): Extra content at the end of the document
When I run a manual backup, it sits at 50% or 60% forever and doesn’t seem to complete its job. I eventually hit Abort.

LOG FILE
[INFO] BackWPup version 3.1.4; A project of Inpsyde GmbH
[INFO] WordPress version 4.2.3
[INFO] Blog url: http://www.dietlowcalorie.com/
[INFO] BackWPup job: Backup1; DBCHECK+DBDUMP+FILE+WPEXP+WPPLUGIN
[INFO] BackWPup no automatic job start configured
[INFO] BackWPup job started manually
[INFO] PHP ver.: 5.4.43 (64bit); cgi-fcgi; Linux
[INFO] Maximum PHP script execution time is 120 seconds
[INFO] Script restart time is configured to 120 seconds
[INFO] MySQL ver.: 5.5.41-cll-lve
[INFO] Web Server: Apache/2.4.12
[INFO] curl ver.: 7.38.0; OpenSSL/1.0.1e
[INFO] Temp folder is: /home/posty4131/public_html/wp-content/uploads/backwpup-1f7fd1-temp/
[INFO] Logfile is: /home/posty4131/public_html/wp-content/uploads/backwpup-1f7fd1-logs/backwpup_log_1f7fd1_2015-08-03_15-20-08.html
[INFO] Backup type is: archive
[INFO] Backup file is: /home/posty4131/public_html/wp-content/uploads/backwpup-1f7fd1-backups/backwpup_1f7fd1_2015-08-03_15-20-08.zip
[03-Aug-2015 15:20:08] 1. Try to backup database …
[03-Aug-2015 15:20:08] Connected to database diet on localhost
[03-Aug-2015 15:20:08] Backup database table “wp_commentmeta” with “2” records
[03-Aug-2015 15:20:08] Backup database table “wp_comments” with “1” records
[03-Aug-2015 15:20:08] Backup database table “wp_dtm_content” with “~0” records
[03-Aug-2015 15:20:08] Backup database table “wp_dtm_root_keywords” with “~0” records
[03-Aug-2015 15:20:08] Backup database table “wp_dtm_seed_keywords” with “~2” records
[03-Aug-2015 15:20:08] Backup database table “wp_dtm_targeted_keywords” with “~0” records
[03-Aug-2015 15:20:08] Backup database table “wp_links” with “7” records
[03-Aug-2015 15:20:08] Backup database table “wp_options” with “672” records
[03-Aug-2015 15:20:08] Backup database table “wp_postmeta” with “6228” records
[03-Aug-2015 15:20:08] Backup database table “wp_posts” with “1855” records
[03-Aug-2015 15:20:22] Backup database table “wp_rssdoodle_keywords” with “~1” records
[03-Aug-2015 15:20:22] Backup database table “wp_rssdoodle_posts” with “~22” records
[03-Aug-2015 15:20:22] Backup database table “wp_sns_backups” with “~0” records
[03-Aug-2015 15:20:22] Backup database table “wp_sns_options” with “~6” records
[03-Aug-2015 15:20:22] Backup database table “wp_sns_settings_destinations” with “~5” records
[03-Aug-2015 15:20:22] Backup database table “wp_sns_state” with “~1” records
[03-Aug-2015 15:20:22] Backup database table “wp_statpress” with “23105” records
[03-Aug-2015 15:20:27] Backup database table “wp_term_relationships” with “3813” records
[03-Aug-2015 15:20:27] Backup database table “wp_term_taxonomy” with “604” records
[03-Aug-2015 15:20:27] Backup database table “wp_terms” with “604” records
[03-Aug-2015 15:20:27] Backup database table “wp_usermeta” with “68” records
[03-Aug-2015 15:20:28] Backup database table “wp_users” with “1” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_campaign” with “1” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_campaign_list” with “1” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_custom_field” with “0” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_email” with “2” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_email_user_stat” with “0” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_email_user_url” with “0” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_form” with “1” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_list” with “2” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_queue” with “0” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_url” with “0” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_url_mail” with “0” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_user” with “1” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_user_field” with “2” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_user_history” with “0” records
[03-Aug-2015 15:20:28] Backup database table “wp_wysija_user_list” with “2” records
[03-Aug-2015 15:20:28] Added database dump “diet.sql” with 20.37 MB to backup file list
[03-Aug-2015 15:20:28] Database backup done!
[03-Aug-2015 15:20:28] Restart will be executed now.
[03-Aug-2015 15:20:28] 1. Trying to make a list of folders to back up …
[03-Aug-2015 15:20:28] 558 folders to backup.
[03-Aug-2015 15:20:28] 1. Trying to create a WordPress export to XML file …
[03-Aug-2015 15:20:47] Check WP Export file …
[03-Aug-2015 15:20:47] WARNING: XML ERROR (1): internal error: Huge input lookup
[03-Aug-2015 15:20:47] WARNING: XML ERROR (5): Extra content at the end of the document
[03-Aug-2015 15:20:47] Added XML export “DietLowCalorie.wordpress.2015-08-03.xml” with 11.38 MB to backup file list.
[03-Aug-2015 15:20:47] Restart will be executed now.
[03-Aug-2015 15:20:48] 1. Trying to generate a file with installed plugin names …
[03-Aug-2015 15:20:48] Added plugin list file “DietLowCalorie.pluginlist.2015-08-03.txt” with 2.02 kB to backup file list.
[03-Aug-2015 15:20:48] 1. Trying to generate a manifest file …
[03-Aug-2015 15:20:48] Added manifest.json file with 5.42 kB to backup file list.
[03-Aug-2015 15:20:48] 1. Trying to create backup archive …
[03-Aug-2015 15:20:48] Compressing files as ZipArchive. Please be patient, this may take a moment.

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