Just ran into this myself last night. So I plugged a thumb drive into a USB port, which came up as drive C and ran the install.Also launched the package using EVClientXXm.MSI /qf. This displays the full installer UI. Don't know if it was necessary...
Yes I have, both in lab and production environments. It works just fine.You will need to reinstall the EVault frontend and backend components on your Exchange servers after the upgrade. The web forms folder path used by the Evault is changed by Exc...