Dropbox error: write tcp [...]:443: wsasend: and EOF

I’m starting a new job of may Thunderbird IMAP folders, that has a total size of ~12 Gb.

I’ve already made backups of other large folders before without problems.

The first backup version has not yet been uploaded, and I’m getting error messages:

Packed Data/profile/ImapMail/imap.gmail-1.com/[Gmail].sbd/Com estrela.msf (10753)
Packing Data/profile/ImapMail/imap.gmail-1.com/[Gmail].sbd/E-mails enviados
Uploaded chunk 80 size 1145776, 153KB/s 18:32:52 4.2%
Skipped chunk 87 size 1203087, 154KB/s 18:29:54 4.3%
Skipped chunk 88 size 2530642, 155KB/s 18:23:43 4.3%
...
Skipped chunk 131 size 1784961, 223KB/s 12:30:59 6.2%
Uploaded chunk 81 size 9363226, 223KB/s 12:28:19 6.3%
Failed to upload the chunk ed06b4e89678dde6219a7fd79b128dbc44807672fdb0f5a8313d55f7f870a480: Post https://content.dropboxapi.com/2/files/upload: write tcp [2804:7f2:2985:8ba9:fd32:da86:7a8c:e597]:26574->[2620:100:601d:8::a27d:508]:443: wsasend: The termination of an existing connection by the remote host was forced.
Incomplete snapshot saved to C:\_Arquivos\Duplicacy\preferences\NOTE4_Admin_ThunderbirdPortable/incomplete

I didn’t identify any connection problems in my router’s log. Was Dropbox that interrupted (“by the remote host was forced”)?

And:

Packed Data/profile/ImapMail/imap.gmail-1.com/[Gmail].sbd/Com estrela (399948)
Packing Data/profile/ImapMail/imap.gmail-1.com/[Gmail].sbd/Com estrela.msf
Packed Data/profile/ImapMail/imap.gmail-1.com/[Gmail].sbd/Com estrela.msf (10753)
Packing Data/profile/ImapMail/imap.gmail-1.com/[Gmail].sbd/E-mails enviados
Skipped chunk 7 size 1203087, 9.86MB/s 00:16:55 0.0%
Skipped chunk 8 size 2530642, 12.27MB/s 00:13:35 0.1%
...
Skipped chunk 50 size 2779108, 105.24MB/s 00:01:34 2.1%
Skipped chunk 51 size 1784961, 106.09MB/s 00:01:33 2.1%
Uploaded chunk 1 size 7519585, 5.62MB/s 00:29:01 2.1%
Uploaded chunk 6 size 7093813, 2.06MB/s 01:19:18 2.2%
Uploaded chunk 52 size 1371580, 1.70MB/s 01:36:02 2.2%
Uploaded chunk 53 size 2992757, 1.26MB/s 02:09:30 2.3%
Uploaded chunk 54 size 2753875, 1.06MB/s 02:33:53 2.3%
Failed to upload the chunk f6687e7c731b8ef7186fc82dfdde2678bb712f7a9033739a7a65ab6b4c92bf19: Post https://content.dropboxapi.com/2/files/upload: EOF
Incomplete snapshot saved to C:\_Arquivos\Duplicacy\preferences\NOTE4_Admin_ThunderbirdPortable/incomplete

I didn’t understand which file the EOF message refers to … the chunk 54?

EOF just means the https connection was closed. I think in both cases the cause was the same – the remote server closed the https connection. I don’t know why the connection was closed, but it should try to catch the error and retry a few times.

Since yesterday I’m running into this error (443) again, now with another file:

...
Uploaded chunk 36 size 2742595, 595KB/s 11:34:27 1.1%
Uploaded chunk 37 size 3215402, 589KB/s 11:45:41 1.1%
Uploaded chunk 38 size 11433463, 575KB/s 12:10:53 1.2%
Failed to upload the chunk ...
Post https://content.dropboxapi.com/2/files/upload: read tcp [....]:443
wsarecv: An established connection was aborted by the software on the host computer.
Incomplete snapshot saved to \Duplicacy\..../incomplete

Aspects in common with the previous occurrence:

  • both times with the Dropbox
  • both times with large files (in this case around 400 Mb, a sqlite DB)

I wonder if the problem is related to Dropbox or file size?

I interrupted the job yesterday and today started it again, but the error reappeared after about 10 minutes.