Last days I've been dealing with an strange issue when a user coudn't complete a syncronization between Outlook and Zimbra.
First sync was completed, but not incremental after this first sync. So user couldn't send or receive emails.
Profile deletion didn't work.

Error given by Outlook was:

This e-mail was generated for technical support purposes.

Sync Type: Delta Sync

Sync Token (before request): 2943360

Sync Token (most current): 2943360

Store: Zimbra - BLABLABLABLA

Computer Name: BLABLABLA

Version: 5.0.3191.20

Error IDs:
id (3) type(folder)
After a deep investigation, enable debugging and contacting Zimbra support without success we found some issues related to localized spanish folder names.

User had already a folder called "Papelera" (trash), probably created at IMAP level by another mail agent.
Trash folder didn't had flag "*" enabled.

So we deleted "Papelera" folder via zmmailbox:

/opt/zimbra/bin/zmmailbox -z -m user@domain gaf
--- in order to locate folder ID ---
/opt/zimbra/bin/zmmailbox -z -m user@domain df folder_id
Then set properly trash folder flags
/opt/zimbra/bin/zmmailbox -z -m user@domain mff Trash "*"
And finally delete zimbra.idm file in Outlook (Located at Application Data or AppData if you are using Windows 7)

And problem fixed.

I hope this helps somebody else in the future.