Active workflow not working with message "Forbidden - perhaps check your credentials?"

[Melissa_BR]

Describe the problem/error/question

We use N8N to forward emails from an SNS queue to customer.IO to send emails. One day, our monitoring alerted us that no email were sent anymore.
We connected to n8n (Cloud version) and realized that most of our workflows had a “warning” sign next to them (see screenshot).

When we opened it and clicked on the warning sign, we got the following message : “Problem activating workflow
The following error occurred on workflow activation:
Forbidden - perhaps check your credentials?” (see screenshot)

Just deactivating and reactivating the workflows solved the issue and the executions started to be processed again.

Additional information

It happened twice in 4 days, once on Friday January 3rd and a second time on Monday January 6th.

Question

What could be the cause of it and how to avoid this ?

Information on your n8n setup

• n8n version: 1.68.0
• n8n EXECUTIONS_PROCESS setting (default: own, main): do not know
• Running n8n via (Docker, npm, n8n cloud, desktop app): n8n Cloud

[n8n]

It looks like your topic is missing some important information. Could you provide the following if applicable.

• n8n version:
• Database (default: SQLite):
• n8n EXECUTIONS_PROCESS setting (default: own, main):
• Running n8n via (Docker, npm, n8n cloud, desktop app):
• Operating system:

[ria]

Hi @Melissa_BR

Thanks for posting here and welcome to the community!
I can’t really see from you screenshots which node/ credentials causes this error.

When a workflow is active but there’s a problem with the credentials used in that workflow, you would get this warning. Usually testing the credentials and if necessary re-configuring them would help as well.

Did you restart the instance as well?

[Melissa_BR]

Hello,

Thank you for your feedback. The credentials were just fine as deactivating and reactivating the workflow solved the issue without changing them.

The instance is a cloud one, I’m not sure we have the control to restart it ?