The Gateway daemon fails to start because the address space where it runs has previously been used for running non program-controlled code.
The Gateway daemon fails to start with the following error:
CTG9549E Gateway daemon failed to start, see Gateway error log; the log location is defined by configuration file file name
The CICS Transaction Gateway HFS (Hierarchical File Store) is mounted with NOSETUID.
Ensure that HFS is mounted with the default of SETUID.