EmailReadImap workflow randomly stop

[rottmann]

I use a "EmailReadImap" node in many workflows and they reconnect every 5 minutes to different sever.
I can see a reconnect every 5 minutes in the mailservers log-files, so far everything is ok.

n8n sometimes re-initialize all workflows (on cleanup log? or sqlite? i don't know).

But sometimes one workflow with EmailReadImap is not re-initialized.

From log (simplified, without other json-data)

Initializing n8n process
Initializing active workflow "mail1"
Successfully activated workflow "mail1"
Successfully started workflow "mail1"
Initializing active workflow "mail2"
Successfully activated workflow "mail2"
Successfully started workflow "mail2"
.
.
.
Initializing active workflow "mail47"
Loaded static data for node "EmailReadImap"
error Unable to initialize workflow "mail47"

If this happen, the workflow "mail47" is shown as "stopped". But in the mailserver logfile i can still see every 5 minute a reconnection.

When i manually stop workflow "mail47" it is stopped and the server logfile has no further reconnection entry.

The problem occur sometimes when n8n re-initialize the workflows and can't automatically restart one workflow.

It seems that EmailReadImap still runs in background and n8n could not start a new process with that workflow. All other workflow with EmailReadImap restarts.
Then the workflow "mail47" is marked as stopped.

EmailReadImap is still running, it reconnects every 5 minute to the server, but the remaining workflow will not be executed, even if a new email arrive. It only reconnects every 5 minutes, although the workflow is not active.

I use these scripts since 1 year, they run until version XXX without any problem. I updated n8n ~2 month ago so i could not say which version XXX exactly was. The problem occurred since that update. I updated last week to version 0.186.1 and the problem happened now again.

To Reproduce

I can't reproduce it.

What i can say is, that all server run and could be accessed, no blocking, no firewall-problem. There is no other error in any log. Mails come in, mails go out.

Environment

• OS: Ubuntu Linux 20.04
• n8n Version 0.186.1
• Node.js Version 16 (docker image n8nio/n8n:latest)
• Database system SQLite
• Operation mode own

[rottmann]

Happened again, now with an another n8n Workflow with an external mail provider, but with EMailReadImap node.

Workflow stopped 2022-08-08 17:00:49

Message (when you click the red triangle)
"Problem activating workflow
The following error occurred on workflow activation:
There was a problem activating the workflow"

Every time this happens, it creates smaller / new log files:

-rw-r--r-- 1 1000 1000 16623714 Jul  2 09:44 n8n110.log
-rw-r--r-- 1 1000 1000 16777859 Jul  4 00:00 n8n.log
-rw-r--r-- 1 1000 1000 16778550 Jul  5 14:00 n8n3.log
-rw-r--r-- 1 1000 1000 16777513 Jul  7 04:10 n8n10.log
-rw-r--r-- 1 1000 1000 16778429 Jul  8 18:25 n8n41.log
-rw-r--r-- 1 1000 1000 16778588 Jul 10 16:25 n8n1.log
-rw-r--r-- 1 1000 1000 16779231 Jul 12 10:10 n8n8.log
-rw-r--r-- 1 1000 1000 16778464 Jul 14 00:45 n8n43.log
-rw-r--r-- 1 1000 1000 16779668 Jul 15 18:35 n8n49.log
-rw-r--r-- 1 1000 1000  6466178 Jul 16 10:41 n8n61.log  <----
-rw-r--r-- 1 1000 1000 16777588 Jul 18 00:27 n8n2.log
-rw-r--r-- 1 1000 1000 16777266 Jul 19 14:18 n8n4.log
-rw-r--r-- 1 1000 1000 16777278 Jul 21 01:16 n8n5.log
-rw-r--r-- 1 1000 1000 16779784 Jul 22 12:20 n8n6.log
-rw-r--r-- 1 1000 1000 16778123 Jul 22 17:35 n8n44.log
-rw-r--r-- 1 1000 1000 16777711 Jul 24 04:49 n8n51.log
-rw-r--r-- 1 1000 1000 16777774 Jul 25 15:59 n8n56.log
-rw-r--r-- 1 1000 1000 16778541 Jul 27 03:00 n8n59.log
-rw-r--r-- 1 1000 1000 10830563 Jul 28 01:44 n8n68.log  <----
-rw-r--r-- 1 1000 1000 16778041 Jul 29 12:30 n8n7.log
-rw-r--r-- 1 1000 1000 16777726 Jul 30 23:31 n8n45.log
-rw-r--r-- 1 1000 1000 16778712 Aug  1 03:30 n8n48.log
-rw-r--r-- 1 1000 1000 16777341 Aug  2 14:30 n8n57.log
-rw-r--r-- 1 1000 1000 16778020 Aug  4 01:40 n8n58.log
-rw-r--r-- 1 1000 1000 16778677 Aug  5 12:55 n8n63.log
-rw-r--r-- 1 1000 1000 16777288 Aug  6 23:46 n8n71.log
-rw-r--r-- 1 1000 1000 16778308 Aug  8 10:45 n8n72.log
-rw-r--r-- 1 1000 1000  3047923 Aug  8 17:05 n8n79.log <----
-rw-r--r-- 1 1000 1000 16459743 Aug 10 09:35 n8n9.log

[rottmann]

Till now since 0.189.1 the problem did not occur again.