Attempting an upgrade to NSX 4.1.2.3 with NSX Application Platform (NAPP) 4.1.1 or earlier will result in a pre-check failure with the following UI message
Cause:
NSX 4.1.2.3 is not compatible with NSX Application Platform version 4.1.1 or earlier.
Note:
a. The incompatibility does not impact customers who have not deployed NAPP, and can successfully continue to upgrade NSX from the previous version to NSX 4.1.2.3
b. Greenfield deployments of NSX 4.1.2.3 cannot install any version of NAPP. An attempt to install NAPP (4.1.1 or earlier) will result in the following UI message
VMware by Broadcom is working on a NAPP release that is compatible with NSX 4.1.2.3. Please contact Broadcom Support for further details.