SMTP not working

[lukasheinz92]

Hello, I use following SMTP config:

SMTP_USERNAME=<123456789>@smtp-brevo.com
SMTP_PASSWORD=*********
SMTP_HOST=smtp-relay.brevo.com
SMTP_PORT=587

When I click to sign in or resend code in the app, I don't get any email. I don't even see any logs in brevo.com. The identity server shows this log every time I try to sign in or resend code:

fail: IdentityServer4.Validation.TokenValidator[0]
      Checking for expected scope IdentityServerApi failed
      {
        "ValidateLifetime": true,
        "AccessTokenType": "Jwt",
        "ExpectedScope": "IdentityServerApi",
        "JwtId": "A63BB48E488F020762C2343F13D9CED3",
        "Claims": {
          "nbf": 1758991602,
          "exp": 1758992802,
          "iss": "http://identity-server:8264",
          "client_id": "notesnook",
          "sub": "68d814eb0b7ed2d6fcfbbd24",
          "auth_time": 1758991596,
          "idp": "local",
          "jti": "A63BB48E488F020762C2343F13D9CED3",
          "iat": 1758991596,
          "scope": "auth:grant_types:mfa"
}
      }

I checked existing issues on GitHub and tried to debug with AI, nothing helped. Thank you.

[vhaudiquet]

I'm having the same issue. I can't seem to fix it even when reverting to an older image, which is weird.

[ikesler]

I also had issues with SMTP and found out an undocumented env variable NOTESNOOK_SENDER_EMAIL which is basically the "from" address for email communication. Without setting it, sender email will be equal to SMTP_USERNAME as far as I understood. For me, it was not good because my SMTP server username was not a valid email.

[lukasheinz92]

@ikesler setting the NOTESNOOK_SENDER_EMAIL variable unfortunatelly didn't resolve the problem.

[audricd]

I also had issues with SMTP and found out an undocumented env variable NOTESNOOK_SENDER_EMAIL which is basically the "from" address for email communication. Without setting it, sender email will be equal to SMTP_USERNAME as far as I understood. For me, it was not good because my SMTP server username was not a valid email.

this isnt working for me either.

my smtp config:

# Description: Username for the SMTP connection (most time it is the email address of your account). Check your email provider's documentation to get the appropriate value.
# Required: yes
NOTESNOOK_SENDER_EMAIL=admin@mail.lab
SMTP_USERNAME=admin@mail.lab
# Description: Password for the SMTP connection. Check your email provider's documentation to get the appropriate value.
# Required: yes
SMTP_PASSWORD=password
# Description: Host on which the the SMTP connection is running. Check your email provider's documentation to get the appropriate value.
# Required: yes
# Example: smtp.gmail.com
SMTP_HOST=mail.lab
# Description: Port on which the the SMTP connection is running. Check your email provider's documentation to get the appropriate value.
# Required: yes
# Example: 465
SMTP_PORT=587

my identity logs:
root@notes:~# docker logs notes-identity-server-1

warn: Microsoft.AspNetCore.DataProtection.Repositories.FileSystemXmlRepository[60]
      Storing keys in a directory '/app/.aspnet/DataProtection-Keys' that may not be persisted outside of the container. Protected data will be unavailable when container is destroyed. For more information go to https://aka.ms/aspnet/dataprotectionwarning
warn: Microsoft.AspNetCore.DataProtection.KeyManagement.XmlKeyManager[35]
      No XML encryptor configured. Key {eee528e1-4b73-4b4a-a406-4122e339d0fc} may be persisted to storage in unencrypted form.
warn: Microsoft.AspNetCore.Server.Kestrel[0]
      Overriding address(es) 'http://*:8080'. Binding to endpoints defined via IConfiguration and/or UseKestrel() instead.
warn: Microsoft.AspNetCore.HttpOverrides.ForwardedHeadersMiddleware[1]
      Unknown proxy: [::ffff:192.168.236.101]:55428

my mail logs:

2025-11-04T19:11:57.328598+01:00 mail dovecot: imap-login: Login: user=<admin@mail.lab>, method=PLAIN, rip=192.168.236.1, lip=172.18.0.3, mpid=1838937, TLS, session=<xDt3xMhCLrnAqOwB>
2025-11-04T19:13:05.647280+01:00 mail dovecot: imap(admin@mail.lab)<1838937><xDt3xMhCLrnAqOwB>: Disconnected: Logged out in=433 out=2755 deleted=0 expunged=0 trashed=0 hdr_count=0 hdr_bytes=0 body_count=0 body_bytes=0
2025-11-04T19:13:05.651399+01:00 mail dovecot: imap(root@mail.lab)<1838936><iit3xMhCLLnAqOwB>: Disconnected: Logged out in=485 out=3409 deleted=0 expunged=0 trashed=0 hdr_count=0 hdr_bytes=0 body_count=0 body_bytes=0