Some NSX services do not support a direct upgrade. In these cases, you must uninstall and reinstall the services.
VMware Partner Security Virtual Appliances
Check the partner documentation to verify if the partner security virtual appliance can be upgraded.
NSX SSL VPN
Starting in NSX 6.2, the SSL VPN gateway only accepts the TLS protocol. However, after upgrading to NSX 6.2 or later, any new clients that you create automatically use the TLS protocol during connection establishment. Additionally, starting in NSX 6.2.3 TLS 1.0 is deprecated.
Because of the protocol change, when an NSX 6.0.x client tries to connect to an NSX 6.2 or later gateway, the connection establishment fails at the SSL handshake step.
After the upgrade from NSX 6.0.x, uninstall your old SSL VPN clients and install the NSX 6.3.x version of the SSL VPN clients. See "Install SSL Client on Remote Site" in the NSX Administration Guide.
NSX L2 VPN
NSX Edge upgrade is not supported if you have L2 VPN installed on an NSX Edge with NSX 6.0.x installed. Any L2 VPN configuration must be deleted before you can upgrade the NSX Edge.