twjeffries

OK! Once I figured it out, the solution was simple.
I used UpdraftPlus “Setings” to switch the remote storage from Dropbox to Google.
The backup worked the first time.

Two of my backups have not finished. When I try to delete them, it says that they do not exist

The error seems to be in writing the files to Dropbox:

0111.131 (0) Saving backup history. Total backup size: 112 MB
0111.140 (0) Requesting upload of the files that have not yet been successfully uploaded (5)
0111.148 (0) Cloud backup selection (1/1): dropbox with instance (1/1) (last)
0111.151 (0) Beginning dispatch of backup to remote (dropbox) (instance identifier s-d2d11a42e5db4dd981de98a1492a6ba1)
0111.153 (0) Dropbox: begin cloud upload (using API version 2 with OAuth v2 token)
0111.179 (0) Dropbox: access gained; setting chunk size to: 1024 KB
0111.440 (0) Dropbox: account/info did not return HTTP 200; returned: 401
0111.444 (0) Dropbox: Attempt to upload: backup_2019-06-05-1543_Xylome_567955872172-plugins.zip to: backup_2019-06-05-1543_Xylome_567955872172-plugins.zip
0112.176 (0) Dropbox: chunked upload exception (Dropbox_BadRequestException): Error in call to API function “files/upload_session/append:2”: HTTP header “Dropbox-API-Arg”: cursor.session_id: ‘None’ expected to be a string, got null (line: 220, file: /data/14/1/151/20/1314509/user/1407950/htdocs/wordpress/wp-content/plugins/updraftplus/includes/Dropbox2/OAuth/Consumer/Curl.php)
0112.179 (0) An error condition has occurred for the first time during this job
0115.916 (0) Dropbox: account/info did not return HTTP 200; returned: 401
0115.919 (0) Dropbox: Attempt to upload: backup_2019-06-05-1543_Xylome_567955872172-themes.zip to: backup_2019-06-05-1543_Xylome_567955872172-themes.zip
0116.603 (0) Dropbox: chunked upload exception (Dropbox_BadRequestException): Error in call to API function “files/upload_session/append:2”: HTTP header “Dropbox-API-Arg”: cursor.session_id: ‘None’ expected to be a string, got null (line: 220, file: /data/14/1/151/20/1314509/user/1407950/htdocs/wordpress/wp-content/plugins/updraftplus/includes/Dropbox2/OAuth/Consumer/Curl.php)
0120.003 (0) Dropbox: account/info did not return HTTP 200; returned: 401
0120.007 (0) Dropbox: Attempt to upload: backup_2019-06-05-1543_Xylome_567955872172-uploads.zip to: backup_2019-06-05-1543_Xylome_567955872172-uploads.zip
0121.102 (0) Dropbox: chunked upload exception (Dropbox_BadRequestException): Error in call to API function “files/upload_session/append:2”: HTTP header “Dropbox-API-Arg”: cursor.session_id: ‘None’ expected to be a string, got null (line: 220, file: /data/14/1/151/20/1314509/user/1407950/htdocs/wordpress/wp-content/plugins/updraftplus/includes/Dropbox2/OAuth/Consumer/Curl.php)
0124.824 (0) Dropbox: account/info did not return HTTP 200; returned: 401
0124.934 (0) Dropbox: Attempt to upload: backup_2019-06-05-1543_Xylome_567955872172-others.zip to: backup_2019-06-05-1543_Xylome_567955872172-others.zip
0125.249 (0) Dropbox: chunked upload exception (Dropbox_BadRequestException): Error in call to API function “files/upload_session/finish”: HTTP header “Dropbox-API-Arg”: cursor.session_id: ‘None’ expected to be a string, got null (line: 220, file: /data/14/1/151/20/1314509/user/1407950/htdocs/wordpress/wp-content/plugins/updraftplus/includes/Dropbox2/OAuth/Consumer/Curl.php)
0125.543 (0) Dropbox: account/info did not return HTTP 200; returned: 401
0125.546 (0) Dropbox: Attempt to upload: backup_2019-06-05-1543_Xylome_567955872172-db.gz to: backup_2019-06-05-1543_Xylome_567955872172-db.gz
0126.093 (0) Dropbox: chunked upload exception (Dropbox_BadRequestException): Error in call to API function “files/upload_session/finish”: HTTP header “Dropbox-API-Arg”: cursor.session_id: ‘None’ expected to be a string, got null (line: 220, file: /data/14/1/151/20/1314509/user/1407950/htdocs/wordpress/wp-content/plugins/updraftplus/includes/Dropbox2/OAuth/Consumer/Curl.php)
0126.099 (0) Retain: beginning examination of existing backup sets; user setting: retain_files=2, retain_db=2