If you have a serial number, then the simplest way to enter it is to start Dyalog APL and run
⎕SE.Dyalog.Serial snwhere sn is your serial number.
The serial number mechanism is implemented using the configuration parameter/environment variable DYALOG_SERIAL; as long as it is set before a Dyalog APL process is started, it will be picked up. There are various ways of entering the serial number, depending on the platform you are running on, and more details appear in the following manuals:
- Dyalog for Microsoft Windows Installation and Configuration Guide
Dyalog for UNIX Installation and Configuration Guide
Dyalog for macOS Installation and Configuration Guide
Dyalog for Raspberry Pi User Guide
The details can also be found on https://help.dyalog.com for Windows, and for all non-Windows platforms.
If you have downloaded Dyalog APL without registering, you can always register at a later date by going to https://www.dyalog.com/download-zone.htm, accepting the conditions and clicking on Register.
Note: Using or entering a serial number other than the one issued to you is not permitted. Transferring the serial number to anyone else is not permitted. For the full licence terms and conditions, see: https://www.dyalog.com/uploads/documents/Terms_and_Conditions.pdf