I have a suspicion: it seems that the problem concerns the color categories...
It seems like SmarterMail doesn't store them properly...
I noticed this because, since everything seemed OK in the webmail, I redid the entire procedure described above FROM scratch, but without doing the Resync All Protocols
Now that I have the WEBMAIL again, with all the correct data (including the colored categories, as shown in the image in the previous post), I to completely delete the Outlook profile (following the guide).
Then I created a new Outlook profile from scratch and synchronized it with SmarterMail via MAPI.
Now everything works without Conflict Errors, but again I lost all the Colored Categories, both in WebMail and in Outlook, as you can see in the images here:
NOTA I'm on MS Outlook LTSC 2021, Italian Version, 64bit
Gabriele Maoret - Head of SysAdmins at SERSIS
Currently manages 6 SmarterMail installations (1 in the cloud for SERSIS which provides services to a few hundred third-party email domains + 5 on-premise for customers who prefer to have their mail server in-house)