Vault cache synchronization failed

Users Vault cache synch failling and trying /evanon VD. (Outlook 2013 with evclient 12.2 /11.0.x)

Based on client log below, i think our users vault cache synchronization is failling because the vault cache is trying to use /evanon virtual directory at some point...i think this is incorrect, it should always use /enterprisevault. 

Look forward to the support.

Please note, we have not allowed http://eeeeee.domain.local/enterprisevault communication in our enviroment. It is blocked  intentionally.

Internally/externally EV Client always communicate with EV server on (https://archive.external.com/enterprisevault).

Env: ev 12.2 + ex2013 cu17 (recently upgraded from ev 11.0.1.ch5 to 12.2)

Client log:

HDR:SYNC: Pre-processing.  Type:MANUALLY INITIATED

26/09/2017 07:50:51.90 Could not contact the EV web server (http://eeeeee.domain.local/enterprisevault) directly

26/09/2017 07:5 Trying the Alternative Web Application URL (https://archive.external.com/enterprisevault)

26/09/2017 07:50:51 Successfully contacted the EV web server using: https://archive.external.com/enterprisevault

26/09/2017 07:51:12HDR: Could not contact the EV web server (http://eeeeee.domain.local/enterprisevault) directly

26/09/2017 07:51:12. HDR: Trying the Alternative Web Application URL (https://archive.external.com/enterprisevault)

26/09/2017 07:5 HDR: Successfully contacted the EV web server using: https://archive.external.com/enterprisevault

26/09/2017 07:51:12.918[9116][H]: HDR:SYNC: Updating MDC map

26/09/2017 07:51:12.918[9116][H]: HDR:SYNC: Getting accessible archives

26/09/2017 HDR: Requesting page: ListArchives.aspx?x==evoutlookext&evhost=http://eeeeee.domain.local/evanon

26/09/2017 07:51:12.925[9116][H]: HDR:SYNC: Error (COM) synchronizing: 0xFFFFFFFF

26/09/2017 07:51:12.925[9116][H]: HDR:SYNC: Failed

26/09/2017 07:51:16.252[1820][H]: HaveConnection::CallBack - HttpQueryInfo failed 0x80070006 (6) : The handle is invalid.

DGO