On Solaris platforms, earlier versions of SSH Tectia Client should be removed before installing SSH Tectia Client 5.x. (When installing via SSH Tectia Manager, this is handled automatically.)
On other platforms, SSH Tectia Client can be upgraded from a previous 5.x installation to a later 5.x simply by installing the newer version of the software on top of the older version.
If installed on the same machine, SSH Tectia Client and SSH Tectia Server 5.x should be always upgraded at the same time, because there are dependencies between the common components.
The old 5.x configuration files are automatically backed up during the upgrade. The backups are stored in the "