IMAP node doesn't work anymore due to Removed triggers and pollers for workflow

[Gnzkj]

Describe the problem/error/question

Note: I have seen other threads about some similar topic, they basically suggest to create a new workflow, create the “Email trigger (IMAP)” node and copy the rest of previous workflow to new one. It works for some time, and then I get same error again…

I am running a workflow that works (for a while). It is deployed via docker-compose.
The workflow as a “Email trigger (IMAP)” node and I suspect it is the reason why part of it won’t work after some time.

Work flow consists of :
part 1 : wait if there is a new email, if so, save some info in a DB
part 2 : wait if there is a webhook call, if so, call the DB and return in the webhook.

Part 2 works well.
Part 1 works for some time, after a while it doesn’t anymore (in the sense that if I send emails to the email address, at first it triggers the Part 1 of the workflow, after some time it has no impact at all on the workflow, no error on the frontend n8n)

What is the error message (if any)?

In the “docker logs <container_id>” logs I see
Removed triggers and pollers for workflow "<id_of_workflow>"
Failed to renew license: renewal failed because current cert is not initialized

note that in my docker-compose i have set up a value for the environement variable N8N_ENCRYPTION_KEY for the n8n service… so unsure about that second error in the logs.

Please share your workflow

Share the output returned by the last node

Part 2 is not connected to Part 1. Part 2 works great.
Part 1 is not triggered at all, no error, no output.

Information on your n8n setup

• n8n version: 1.47.1
• Database (default: SQLite): Postgres
• n8n EXECUTIONS_PROCESS setting (default: own, main): unsure where to look for this info ?
• Running n8n via (Docker, npm, n8n cloud, desktop app): docker-compose
• Operating system: Ubuntu on Hetzner VPS

Any permanent fix help is welcome, even a “trick” to make it work by having something else to trigger the IMAP node on a frequent basis to do the trick…
Was thinking about maybe using the Gmail node but it needs an API account and I feel it is a paid thing and would like to reduce more dependencies…

[mariana-na]

Hi @Gnzkj ,

Welcome to the community!

I’m sorry you’re having these issues. Let’s go through them in parts.

From the errors you’re seeing only the first one is related to this issue. Failed to renew license: renewal failed because current cert is not initialized is related to not having an Enterprise license. It comes up whenever you go into the Usage and Plan page because that’s where n8n checks for the enterprise license and renews it. Even though this looks a bit ominous it actually doesn’t affect your instance

Removed triggers and pollers for workflow "<id_of_workflow>" tends to be related to heavy traffic in a workflow. Things like memory, execution overlaps or very large wfs.
From what I understood your workflow has extra steps after the IMAP node, no? Would it be possible to share those, just to get an idea of the actual size of the wf?

Additionally, is part 2 a second parallel workflow? As in, an independent wf in the same editor?

[Gnzkj]

Thanks a lot for the welcome as well as for the detailed answer. Much appreciated.

Regarding the “license” error all clear

About the “triggers and pollers” error: I am alone on this workflow, and did some tests, probably like 20 or so…
The workflow is not that large (in my opinion) and the 2 parts are in the same workflow, just not connected.

Maybe due to my server ? I’m not thinking traffic as bandwidth, nor space as hard drive, but maybe CPU or RAM as I have other docker running ?
but then, even so, after some time it should calms down…and it didnt seem to. It was just hanged up…

Here is the workflow: