Need some help with 2 grommunio-sync users.

Rene

I had some issues with one of the previous upgrades ( a while back) and that was a fun learning experience, build a second mailserver, moved user from server a to server b, getting the DKIM right again, resetting al the SPAM settings et al.

Yet, the issue I had after the upgrade still remains,.. I've got 2 users that generate a lot of grommunio-sync errors.

29/04/2026 09:51:49 [ 4584] [ INFO] [serge.***********@*****.nl] cmd='Ping' memory='5.59 MiB/6.00 MiB' time='180.63s' devType='Outlook' devId='a62554cd8c9245d6a34b2a31f4c25151' getUser='*****.nl\serge.***********@*****.nl' from='40.99.214.125' idle='180s' version='2.4.8.483c521' method='POST' httpcode='200' 29/04/2026 10:55:20 [21820] [ WARN] [#serge.***********@*****.nl] IP: 40.99.214.125 failed to authenticate user '*****.nl\serge.***********@*****.nl' 29/04/2026 10:55:20 [21820] [ INFO] [#serge.***********@*****.nl] cmd='Options' memory='2.28 MiB/6.00 MiB' time='0.01s' devType='Outlook' devId='a62554cd8c9245d6a34b2a31f4c25151' getUser='*****.nl\serge.***********@*****.nl' from='40.99.214.125' idle='0s' version='2.4.8.483c521' method='OPTIONS' httpcode='401'
This also generates issues in the administrative 'mobile devices' view.

I've deleted the associated devices from the users, and instructed them to remove their configured account(s) from their phone(s), unfoirtunately when they (re)create their account the issue also returns. Do you guys have any thoughts about this ( yes unfortunately they -still- use outlook on their phones, but it also happens with a 'real' activesync account).

When the mobile device admin view is working, I can see that teh devices for those uses do sync (the users themselves don't complain about it, but I would like to get rid of the errors)

versions;
grommunio-admin-api 1.18.8.m31adda4 lp156.11.1 grommunio-admin-common 50.10f1afb lp156.51.1 grommunio-admin-web 5.0.0.28.19b1c07 lp156.169.1 grommunio-antispam 4.0.1 lp156.4.1 grommunio-common 29.8 lp156.13.1 grommunio-cui 1.1.3.b0091e0 lp156.6.1 grommunio-dav 1.6.24.84942ef lp156.1.1 grommunio-dbconf 1.1.2.4bbae9a lp156.15.1 grommunio-error-pages 1.0.10.bb2df37 lp156.31.1 grommunio-imapsync 2.314 lp156.1.1 grommunio-index 1.5.0.gb0a01b9 lp156.2.1 grommunio-release 2025.1.2 lp156.8.1 grommunio-setup 1.1.16.46f2af3 lp156.73.1 grommunio-sync 2.4.8.483c521 lp156.23.1 grommunio-web 3.17.271.gce4f0824d lp156.458.1 gromox 3.6.55.mab2f038 lp156.40.1 gromox-debuginfo 3.6.55.mab2f038 lp156.40.1 gromox-debugsource 3.6.55.mab2f038 lp156.40.1 grub2-theme-grommunio 1 lp156.21.1 joe 4.6 lp156.2.4 libbfio1 20240414 lp156.1.2 libesedb1 20240420 lp156.3.2 libexmdbpp0 1.11.17.14d8ad1 lp156.308.1 libHX32 4.27 lp156.1.1 libHX43 5.4 lp156.1.1 libolecf1 20240427 lp156.2.2 libpff1 20231205 lp156.2.2 libtinyxml2-10 10.0.0 lp156.2.2 libwmime2 1.0.0 lp156.3.2 mapi-header-php 2.1.15.2966759 lp156.6.1 nginx-module-brotli 1.0.0rc+git9 lp156.1.2 nginx-module-vts 0.2.5 lp156.1.1 patterns-grommunio 1 lp156.10.1 perl-Authen-NTLM 1.09 lp156.1.1 perl-Encode-IMAPUTF7 1.70.0 lp156.1.1 perl-IO-Tee 0.66 lp156.1.1 perl-JSON-WebToken 0.10 lp156.3.1 perl-Mail-IMAPClient 3.43 lp156.1.1 plymouth-theme-grommunio 1 lp156.20.1 python311-mattermostdriver 7.3.2 lp156.19.1 python311-mysqlclient 1.4.6 lp156.3.3 python311-openapi-core 0.13.7 lp156.13.2 python311-openapi-schema-validator 0.1.5 lp156.11.4 python311-openapi-spec-validator 0.2.9 lp156.12.1 python311-parse 1.21.1 lp156.1.1 python311-pyexmdb 1.11.17.14d8ad1 lp156.308.1 python311-systemd 235 lp156.2.2 python311-uwsgi-python3 2.0.31 lp156.1.6 python3-mattermostdriver 7.3.2 lp156.15.2 python3-openapi-core 0.13.7 lp156.8.1 python3-openapi-schema-validator 0.1.5 lp156.11.4 python3-pamela 1.0.0 lp156.4.2 python3-parse 1.15.0 lp156.2.2 python3-pyexmdb 1.11.17.14d8ad1 lp156.308.1 python3-rfc3339-validator 0.1.4 lp156.9.2 systemd-coredump-grommunio 1 lp156.3.1 systemd-presets-branding-grommunio 2024.06 lp156.2.1 system-user-grommunio 10 lp156.6.1 system-user-gromox 9 lp156.6.1 update-alternatives 1.22.18 lp156.5.2 uwsgi 2.0.31 lp156.1.6

Do any of you have any suggestions on where the issue could be located?

-edit- typos

WalterH

What devices are these? What are their models and OS versions?

Rene

One of the devices is a Samsung S22+ unknown version at this moment, the other is a Oneplus 13 on OxygesOS CPH2653_16.0.5.703 ( thats the one from the error snippets.)

I've got an Samsung S25 Ultra Android 16 OneUI 8.0 which is working and syncing fine

btw (all) the user accounts are located in an Microsft AD, and not locked of disabled,

Rene

What i've done so far; I've installed a new appliance, configured it to sync with AD, exported all mailboxes from the old server ( with gromox-exm2mt ) and imported them into the new mailserver (with gromox-import -ctx) to make sure the database is clean and consistent.

the frontend is accessed via an Opnsense HAProxy configuration with LE cert (via automations also made available in Grommunio for internal https access). Grommunio is X-Forwarded-For aware. I've also implemented Fail2Ban from your repository (with an additional opnsense-alias[] banaction for a dynamic opnsense blocklist).

Rene

right, I thought i've read somewhere (sometime ago) about the Android outlook app.. so after some more duckduck Fu it came up with your respons Walter.
https://community.grommunio.com/d/2257-outlook-for-android-creates-multiple-grommunio-sync-fail2ban-errors

so it's time to educate the kids..