OpenScape Office MX V3 releases since OpenScape Office MX V3 R3.2.0 and above have reached a file size which could prevent a successful upgrade from V2 to V3. V2 used to keep recent update file images on the upgrade partition.
V3 introduces a mechanism which cleans the upgrade partition before file transfer is started. This mechanism is missing in V2. Upgrade would be aborted if no more storage space is available.

Unaffected due to a smaller image size and therefore required for successful V2 to V3 migration is to upgrade to the following release V3 R1.2.0 before upgrading to latest OSO V3 releases in case a current release cannot be uploaded to OSO.  Please keep in mind to follow migration instructions according to appropriate ReleaseNote information (Chapter 2) and migration documentation (Chapter 6: Documentation Reference).

Additionally keep in mind: the following settings cannot be automatically migrated in versions < V3 R3.2.0 and need to be reconfigured after upgrade: ‘Email forwarding’, ‘Mobile Login’, ‘Intercept Position’ and ‘Door Opener’.