connecting with imap with my iphone takes forever after Upgrade to 26.3.0

I have the same problems after upgrade, all imap iphones/ just MASS spam logs and they just hang 

Logs give the same LIST

LIST elapsed=0 (NIO)

NAMESPACE elapsed=0 (NIO)

Hello,

Same behavior here.

After upgrading to Carbonio 26, all iPhone IMAP clients are affected:
- Connections succeed but clients hang
- Mailbox appears empty or never loads

Server logs show exactly the same pattern:
- Repeated LIST
- Repeated NAMESPACE
- No SELECT INBOX

Example:
LIST elapsed=0 (NIO)
NAMESPACE elapsed=0 (NIO)

Manual IMAP tests (LOGIN / LIST / SELECT INBOX) work perfectly and confirm that data is present.

This clearly looks like a loop or incompatibility between Apple Mail and Carbonio 26 IMAP handling.

Multiple users are now reporting the same issue, so this does not appear environment-specific.

We have paused upgrades on other environments and are waiting for a fix.

Thanks

Bonjour,

Même comportement ici.

Après la mise à jour vers Carbonio 26, tous les clients IMAP sur iPhone sont impactés :
- La connexion fonctionne mais les clients restent bloqués
- La boîte est vide ou ne se charge jamais

Les logs serveur montrent exactement le même schéma :
- LIST répété
- NAMESPACE répété
- Aucun SELECT INBOX

Exemple :
LIST elapsed=0 (NIO)
NAMESPACE elapsed=0 (NIO)

Les tests IMAP manuels (LOGIN / LIST / SELECT INBOX) fonctionnent parfaitement et confirment que les données sont présentes.

Cela ressemble clairement à une boucle ou une incompatibilité entre Apple Mail et le comportement IMAP de Carbonio 26.

Plusieurs utilisateurs signalent désormais le même problème, ce qui indique que ce n’est pas spécifique à un environnement.

Nous avons suspendu les mises à jour sur nos autres environnements en attendant un correctif.

Merci

@All

Our devs are working on this issue. We hope to fix this with a hotfix soon. I do not have a ETA right now. I would update you again by Friday.

Thanks for your understanding.

Regards,

Hello,

Thank you for the update.

We can confirm the issue is fully reproducible on our side after upgrading to Carbonio CE 26.

========================
ENVIRONMENT
========================
- Carbonio CE 26
- Single server installation

========================
IMPACT
========================
- All Apple Mail clients on iPhone are affected
- Users cannot access their mailbox (empty or never loading)

========================
SYMPTOMS
========================
- IMAP authentication: OK
- SMTP sending: OK
- Webmail: OK
- Apple Mail connects but:
→ mailbox is empty
→ no folders displayed
→ or client hangs indefinitely

========================
IMAP VALIDATION
========================
Manual IMAP tests confirm server is working correctly:
- LOGIN OK
- LIST OK
- SELECT INBOX OK (messages present)

========================
LOG OBSERVATION
========================
From mailbox.log:

imap - cmd=LOGIN
imap - cmd=NAMESPACE
imap - cmd=LIST "" "*"
imap - cmd=NAMESPACE
imap - cmd=LIST "" "*"

The client loops on NAMESPACE and LIST without ever issuing SELECT INBOX.

We also observe:
LIST elapsed=0 (NIO)
NAMESPACE elapsed=0 (NIO)

========================
CONCLUSION
========================
This strongly suggests an IMAP compatibility issue or regression in Carbonio 26 affecting Apple Mail.

We have paused upgrades on other environments and are waiting for the hotfix.

========================
ADDITIONAL INFO
========================
We are available to:
- Provide full mailbox.log extracts
- Run specific tests if needed
- Validate any proposed fix

Thanks for your work on this issue.

Bonjour,

Merci pour votre retour.

Nous confirmons que le problème est entièrement reproductible de notre côté après la mise à jour vers Carbonio CE 26.

========================
ENVIRONNEMENT
========================
- Carbonio CE 26
- Installation mono-serveur

========================
IMPACT
========================
- Tous les clients Apple Mail sur iPhone sont impactés
- Les utilisateurs ne peuvent pas accéder à leur boîte (vide ou bloquée)

========================
SYMPTÔMES
========================
- Authentification IMAP OK
- Envoi SMTP OK
- Webmail OK
- Apple Mail se connecte mais :
→ boîte vide
→ aucun dossier affiché
→ ou blocage du client

========================
VALIDATION IMAP
========================
Les tests IMAP manuels confirment que le serveur fonctionne correctement :
- LOGIN OK
- LIST OK
- SELECT INBOX OK (messages présents)

========================
OBSERVATION DES LOGS
========================
Extrait mailbox.log :

imap - cmd=LOGIN
imap - cmd=NAMESPACE
imap - cmd=LIST "" "*"
imap - cmd=NAMESPACE
imap - cmd=LIST "" "*"

Le client boucle sur NAMESPACE et LIST sans jamais effectuer SELECT INBOX.

Nous observons également :
LIST elapsed=0 (NIO)
NAMESPACE elapsed=0 (NIO)

========================
CONCLUSION
========================
Cela indique fortement un problème de compatibilité IMAP ou une régression dans Carbonio 26 affectant Apple Mail.

Nous avons suspendu les mises à jour sur nos autres environnements en attendant le correctif.

========================
INFORMATIONS COMPLÉMENTAIRES
========================
Nous sommes disponibles pour :
- Fournir des extraits complets de mailbox.log
- Effectuer des tests spécifiques
- Valider un correctif

Merci pour votre travail sur ce sujet.

@sharif 

Thanks !

Nothing to do with this imap problem but FYI. also have a look on my remarks i mentioned before some posts ago about the Carbonio Mail App.

Hello,
Thanks for the update.
Just to clarify on our side:
We did not notice any issue with the Carbonio Mail App during our tests.
Our main blocking issue remains the IMAP behavior with Apple Mail on iPhone after upgrading to Carbonio 26.
The problem is still fully reproducible:
- IMAP login OK
- SMTP OK
- Webmail OK
- But mailbox is empty or not loading on iPhone
We are waiting for the hotfix regarding this IMAP issue.
Thanks

Bonjour,
Merci pour votre retour.
Pour préciser de notre côté :
Nous n’avons constaté aucun problème particulier avec l’application Mail Carbonio lors de nos tests.
Le problème principal bloquant reste le comportement IMAP avec Apple Mail sur iPhone après la mise à jour vers Carbonio 26.
Le problème est toujours entièrement reproductible :
- Authentification IMAP OK
- SMTP OK
- Webmail OK
- Mais boîte vide ou non chargée sur iPhone
Nous sommes en attente du correctif concernant ce problème IMAP.
Merci

I was able to make the iphone get the mail box, by going into the client and finding and older email , deleting it , and then it starts updating. This just forces an update and you get new mails. So its just a work around for the clients.While we wait.

Hello,
Thanks for sharing this workaround.
We tested it on our side and it can indeed trigger a temporary refresh on iPhone, but it is not reliable for all users.
We will keep this as a temporary workaround while waiting for the official hotfix.
Looking forward to the update.
Thanks

Bonjour,
Merci pour le partage de ce contournement.
Nous l’avons testé de notre côté, cela peut effectivement déclencher un rafraîchissement temporaire sur iPhone, mais ce n’est pas fiable pour tous les utilisateurs.
Nous allons l’utiliser comme solution temporaire en attendant le correctif officiel.
Dans l’attente de la mise à jour.
Merci

Hi everyone,

I ran into the same issue, and unfortunately the suggested workaround (opening an old email, deleting it, and waiting for sync to resume) didn’t work in my case.

After some investigation, it looks like Carbonio is having trouble handling pipelined IMAP commands, specifically when NAMESPACE and LIST (with SPECIAL-USE) are sent together by clients like Apple Mail.

🛠 Workaround

To mitigate this, I created a simple JavaScript MITM IMAP proxy that sits between the client and Carbonio:

• It forwards all traffic normally

• When it detects the problematic pattern (NAMESPACE + LIST RETURN ... SPECIAL-USE), it splits them into separate commands

• This makes the request compliant with what Carbonio expects

Everything else is passed through untouched.

⚠️ Important notes

• Apple Mail (especially on iOS) may requires SSL, so you must provide valid certificates

• Mount your SSL folder into the container and configure the environment variables accordingly

• Update the CARBONIO_DNS variable to point to your server

📦 Repository

You can find the implementation here:

Github: Lucas-Ribeiro-Lima removed link

📌 Disclaimer

• This is a temporary workaround, not a permanent fix

• It was quickly developed and tested in a small environment (few IMAP users)

• I cannot guarantee how well it scales under heavy load

The goal is simply to provide an option for those who prefer not to roll back and want to keep things running while waiting for an official fix from Zextras.

Hope this helps someone 👍

services:
  carbonio-imap-hotfix:
    image: lucaslive974/carbonio-imap-hotfix
    container_name: carbonio-imap-hotfix
    ports:
      - "993:9993"
    volumes:
      - /home/lucaslima/Trabalho/ssl:/usr/bin/app/ssl
    environment:
      - NODE_ENV=production
      - SSL_KEY_PATH=. . removed link 
      - SSL_CERT_PATH= . removed link 
      - CARBONIO_DNS=CARBONIO_DNS
      - CARBONIO_IMAP_PORT=993
      - IS_SSL_DISABLED=false
    restart: unless-stopped

Is there no fix yet or ETA ? this is causing lots of troubles.

Hello,
Same situation on our side.
This issue is still impacting all iPhone users and is causing significant disruption in production.
We understand that a hotfix is in progress and we appreciate your work on it.
At this stage, any update or estimated timeframe would really help us plan accordingly.
Thanks

Bonjour,
Même situation de notre côté.
Ce problème impacte toujours tous les utilisateurs iPhone et génère des perturbations importantes en production.
Nous comprenons qu’un correctif est en cours et nous apprécions votre travail sur ce sujet.
À ce stade, toute mise à jour ou estimation de délai nous aiderait à nous organiser.
Merci

Is there any news on the issue? It's very inconvenient to constantly access the web interface to read your mail.

Hello,
Same situation on our side.
This issue is quite impacting in daily use, especially for users relying on iPhone, and using the web interface as a fallback is not a sustainable solution.
We understand a fix is in progress, but any update or ETA would be really helpful at this point.
Thanks

Bonjour,
Même situation de notre côté.
Ce problème est très impactant au quotidien, notamment pour les utilisateurs iPhone, et l’utilisation de l’interface web en solution de secours n’est pas viable sur le long terme.
Nous comprenons qu’un correctif est en cours, mais toute information ou estimation de délai serait vraiment utile à ce stade.
Merci

This appears to be fixed in the latest update (installed today). I am getting some weird messages in the log that I don't remember seeing before though!

2026-04-03 08:43:01,650 WARN  [qtp1611382686-346] [] extensions - unable to find handler for extension: system failure: Extension HTTP handler not found at /metrics/powerstore

Just adding my voice to this as well. Whilst I experienced some other issues in the upgrade which I was able to resolve, this issue is ongoing and I too have rolled back pending a fix.