I installed n8n on Windows using npm install -g n8n.
When I start n8n, I see this error:
[license SDK] license activation failed: request/body/reservationId must match format "uuid"
400 Activation key is in the wrong format
I followed the steps to request a free community license key, but I never received the email (nothing in spam either).
Can you help me get my free activation key manually?
Thank you 
Not receiving the license by email is an ongoing issue, which will be fixed on Monday if not before.
I’m having the same problem.
I still have this problem.
I received a key today.
The issue with not receiving the n8n license code is not resolved. I currently have it.
This is still not working. I have the same issue too.
I got it to work!! In my hosted instance I went to Personal / Workflows. I clicked the icon at right to create a folder and got an error message that I needed to be registered to create folders. I clicked to send a new key and a new key was sent that was different to the old. This new key worked.