Refer to the following conventions applicable for the Apex Central installation or web console configuration.
User names
Max. length: 32 characters
Allowed: A-Z, a-z, 0-9, -, _, ., $
Folder names
Max. length: 32 characters
Not allowed: /, >, &, ", %, ^, =
For the Apex Central server host name, the setup program supports servers with underscores ("_") as part of the server name.