Menu path: File→Tree Save File.
tsave open tree files (with + at the end, append) xxx open in compact (default) mode *xxx open in parentethical notation, using taxon names or numbers (see under "taxname") / close tree file !t xxx autosave results to file, every t seconds (t can be given as hh:mm:ss). For maximum safety, results alternatively saved to files xxx-1 and xxx-2 (if power fails when saving, the previous one remains).
Example: Open a new tree file called "arbol.tre" in compact notation.
Example: Append to an existing tree file called "arbol.tre" in parentethical notation.
See the command "save" for further information.