Please be informed that we are using EV (File and Exchange archive)Version: 18.104.22.16806 and we are goint to upgrade to EV 12. May i know is it correct if I perform as below:
Upgrade EV from Version: 22.214.171.12406->12.0.0->12.2.3 (downlaod Veritas_Enterprise_Vault_12_2_3.zip then install)
That will not work. You should upgrade from 11.0.1 to 12.2.0, then upgrade the SQL databases. Once the databases are upgraded, you can apply the latest maintenance release which is 12.2.3.
12.2.3 is a maintenance release and so can only be applied after you have upgraded to 12.2. (12 = major release, 12.x = minor release, 12.x.y = maintenance release)
Just be aware that EV 12 requires Windows Server 2012, hence if you are running older OS version on the current EV version, you will have to migrate to a new server.