Problem with back-up

I tried configuring Backwpup 3.1.4 to back-up to my dropbox account but it consistently failed with the following error report:

[INFO] BackWPup version 3.1.4; A project of Inpsyde GmbH
[INFO] WordPress version 4.2.2
[INFO] Blog url: https://wokinghamlions.org.uk/
[INFO] BackWPup job: Job with ID 1; DBDUMP+FILE+WPEXP+WPPLUGIN
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[24-Jun-2015 05:17:53] Uploading to Dropbox …
[24-Jun-2015 05:18:49] Restart after 58 seconds.
[24-Jun-2015 05:19:50] Restart after 59 seconds.
[24-Jun-2015 05:20:51] Restart after 60 seconds.
[24-Jun-2015 05:21:08] ERROR: Dropbox API: (500) Internal Server Error
[24-Jun-2015 05:21:08] Restart will be executed now.
[24-Jun-2015 05:21:10] 2. Try to send backup file to Dropbox …
[24-Jun-2015 05:21:11] Authenticated with Dropbox of user Alan Rouse ([email protected])
[24-Jun-2015 05:21:11] 44.90 GB available on your Dropbox
[24-Jun-2015 05:21:11] Uploading to Dropbox …
[24-Jun-2015 05:21:20] ERROR: Dropbox API: (500) Internal Server Error
[24-Jun-2015 05:21:20] Restart will be executed now.
[24-Jun-2015 05:21:21] 3. Try to send backup file to Dropbox …
[24-Jun-2015 05:21:22] Authenticated with Dropbox of user Alan Rouse ([email protected])
[24-Jun-2015 05:21:22] 44.90 GB available on your Dropbox
[24-Jun-2015 05:21:22] Uploading to Dropbox …
[24-Jun-2015 05:21:31] ERROR: Dropbox API: (500) Internal Server Error
[24-Jun-2015 05:21:31] Restart will be executed now.
[24-Jun-2015 05:21:33] ERROR: Step aborted: too many attempts!
[24-Jun-2015 05:21:33] ERROR: Job has ended with errors in 442 seconds. You must resolve the errors for correct execution.

I tried updating to Backwpup 3.2.0-alpha2 and got the following errors:

[INFO] BackWPup 3.2.0-alpha2; A project of Inpsyde GmbH
[INFO] BackWPup job: Job with ID 1
[INFO] Cron: 0 5 * * *; Next: Sat, 27 Jun 2015 @ 05:00
[INFO] Logfile is: backwpup_log_7b2d0f_2015-06-26_05-05-53.html
[INFO] Backup file is: backwpup_Lions_website_2015-06-26_05-05-53.zip
[26-Jun-2015 05:05:53] 1. Try to backup database …
[26-Jun-2015 05:05:53] Connected to database W0k0L10ns on 213.171.200.71
[26-Jun-2015 05:05:54] Added database dump “Lions_Website.sql” with 2.05 MB to backup file list
[26-Jun-2015 05:05:54] Database backup done!
[26-Jun-2015 05:05:54] 1. Trying to make a list of folders to back up …
[26-Jun-2015 05:06:01] 1260 folders to backup.
[26-Jun-2015 05:06:02] 1. Trying to create a WordPress export to XML file …
[26-Jun-2015 05:06:03] Check WP Export file …
[26-Jun-2015 05:06:03] WP Export file is a valid WXR file.
[26-Jun-2015 05:06:03] Added XML export “Wokingham-Lions-Club.wordpress.2015-06-26.xml” with 996.79 kB to backup file list.
[26-Jun-2015 05:06:03] 1. Trying to generate a file with installed plugin names …
[26-Jun-2015 05:06:04] Added plugin list file “Wokingham-Lions-Club.pluginlist.2015-06-26.txt” with 3.29 kB to backup file list.
[26-Jun-2015 05:06:04] 1. Trying to generate a manifest file …
[26-Jun-2015 05:06:04] Added manifest.json file with 6.31 kB to backup file list.
[26-Jun-2015 05:06:04] 1. Trying to create backup archive …
[26-Jun-2015 05:06:04] Compressing files as ZipArchive. Please be patient, this may take a moment.
[26-Jun-2015 05:09:00] Backup archive created.
[26-Jun-2015 05:09:00] Archive size is 600.05 MB.
[26-Jun-2015 05:09:00] 9936 Files with 698.12 MB in Archive.
[26-Jun-2015 05:09:00] 1. Try to send backup file to Dropbox …
[26-Jun-2015 05:09:01] Authenticated with Dropbox of user: Alan Rouse
[26-Jun-2015 05:09:01] Uploading to Dropbox …
[26-Jun-2015 05:10:00] ERROR: Signal “SIGTERM” is sent to script!
[26-Jun-2015 05:10:01] 2. Try to send backup file to Dropbox …
[26-Jun-2015 05:10:02] Authenticated with Dropbox of user: Alan Rouse
[26-Jun-2015 05:10:02] Uploading to Dropbox …
[26-Jun-2015 05:10:05] (400) False offset will corrected
[26-Jun-2015 05:17:04] ERROR: Signal “SIGTERM” is sent to script!
[26-Jun-2015 05:17:05] 3. Try to send backup file to Dropbox …
[26-Jun-2015 05:17:06] Authenticated with Dropbox of user: Alan Rouse
[26-Jun-2015 05:17:06] Uploading to Dropbox …
[26-Jun-2015 05:17:09] (400) False offset will corrected
[26-Jun-2015 05:19:06] ERROR: Signal “SIGTERM” is sent to script!
[26-Jun-2015 05:19:11] (400) False offset will corrected
[26-Jun-2015 05:19:27] ERROR: Dropbox API: (500) Internal Server Error
[26-Jun-2015 05:19:29] ERROR: Step aborted: too many attempts!
[26-Jun-2015 05:19:29] ERROR: Job has ended with errors in 816 seconds. You must resolve the errors for correct execution.

I then tried changing to instead back up to a folder s:/dropbox/Wokingham Lions Website/. Although it doesn’t report any errors, no log file is save in that folder. I tried reverting to Backwepup 3.1.4 and still nothing is created in the destination folder, even though the log doesn’t report any errors:

[INFO] BackWPup version 3.1.4; A project of Inpsyde GmbH
[INFO] WordPress version 4.2.2
[INFO] Blog url: https://www.wokinghamlions.org.uk/
[INFO] BackWPup job: Job with ID 1; DBDUMP+FILE+WPEXP+WPPLUGIN
[INFO] BackWPup cron: 0 5 * * *; Next: Sat, 27 Jun 2015 @ 05:00
[INFO] BackWPup job started manually
[INFO] PHP ver.: 5.4.42 (64bit); cgi-fcgi; Linux
[INFO] Maximum PHP script execution time is 60 seconds
[INFO] Script restart time is configured to 60 seconds
[INFO] MySQL ver.: 5.1.73-log
[INFO] Web Server: Apache
[INFO] curl ver.: 7.15.5; OpenSSL/0.9.8b
[INFO] Temp folder is: /home/linweb25/w/wokinghamlions.org.uk-1073414578/user/htdocs/wp-content/uploads/backwpup-7b2d0f-temp/
[INFO] Logfile is: /home/linweb25/w/wokinghamlions.org.uk-1073414578/user/htdocs/wp-content/uploads/backwpup-7b2d0f-logs/backwpup_log_7b2d0f_2015-06-26_11-11-54.html
[INFO] Backup type is: archive
[INFO] Backup file is: s:/dropbox/Wokingham Lions Website/backwpup_Lions_website_2015-06-26_11-11-54.zip
[26-Jun-2015 11:11:54] 1. Try to backup database …
[26-Jun-2015 11:11:54] Connected to database W0k0L10ns on 213.171.200.71
[26-Jun-2015 11:11:54] Backup database table “wp_commentmeta” with “477” records
[26-Jun-2015 11:11:54] Backup database table “wp_comments” with “243” records
[26-Jun-2015 11:11:54] Backup database table “wp_links” with “0” records
[26-Jun-2015 11:11:54] Backup database table “wp_masterslider_options” with “1” records
[26-Jun-2015 11:11:54] Backup database table “wp_masterslider_sliders” with “11” records
[26-Jun-2015 11:11:54] Backup database table “wp_ngg_album” with “1” records
[26-Jun-2015 11:11:54] Backup database table “wp_ngg_gallery” with “2” records
[26-Jun-2015 11:11:54] Backup database table “wp_ngg_pictures” with “7” records
[26-Jun-2015 11:11:54] Backup database table “wp_options” with “269” records
[26-Jun-2015 11:11:54] Backup database table “wp_postmeta” with “1734” records
[26-Jun-2015 11:11:54] Backup database table “wp_posts” with “777” records
[26-Jun-2015 11:11:55] Backup database table “wp_term_relationships” with “43” records
[26-Jun-2015 11:11:55] Backup database table “wp_term_taxonomy” with “8” records
[26-Jun-2015 11:11:55] Backup database table “wp_terms” with “8” records
[26-Jun-2015 11:11:55] Backup database table “wp_usermeta” with “79” records
[26-Jun-2015 11:11:55] Backup database table “wp_users” with “3” records
[26-Jun-2015 11:11:55] Added database dump “Lions_Website.sql” with 2.05 MB to backup file list
[26-Jun-2015 11:11:55] Database backup done!
[26-Jun-2015 11:11:55] 1. Trying to make a list of folders to back up …
[26-Jun-2015 11:11:55] 1262 folders to backup.
[26-Jun-2015 11:11:55] 1. Trying to create a WordPress export to XML file …
[26-Jun-2015 11:11:57] Check WP Export file …
[26-Jun-2015 11:11:57] WP Export file is a valid WXR file.
[26-Jun-2015 11:11:57] Added XML export “Wokingham-Lions-Club.wordpress.2015-06-26.xml” with 996.79 kB to backup file list.
[26-Jun-2015 11:11:57] 1. Trying to generate a file with installed plugin names …
[26-Jun-2015 11:11:57] Added plugin list file “Wokingham-Lions-Club.pluginlist.2015-06-26.txt” with 3.38 kB to backup file list.
[26-Jun-2015 11:11:57] 1. Trying to generate a manifest file …
[26-Jun-2015 11:11:57] Added manifest.json file with 6.25 kB to backup file list.
[26-Jun-2015 11:11:57] 1. Trying to create backup archive …
[26-Jun-2015 11:11:57] Compressing files as ZipArchive. Please be patient, this may take a moment.
[26-Jun-2015 11:12:56] Restart after 62 seconds.
[26-Jun-2015 11:13:58] Restart after 61 seconds.
[26-Jun-2015 11:14:59] Restart after 60 seconds.
[26-Jun-2015 11:15:15] Backup archive created.
[26-Jun-2015 11:15:15] Archive size is 600.06 MB.
[26-Jun-2015 11:15:15] 10230 Files with 708.46 MB in Archive.
[26-Jun-2015 11:15:15] Restart will be executed now.
[26-Jun-2015 11:15:16] Job done in 202 seconds.

What am I doing werong?

https://www.ads-software.com/plugins/backwpup/