thanx so much. Both methods work perfectly.

there’s a way in a txt file to delete all lines that do NOT contain a specific phrase?
For example in a text file I want to remove all lines that do NOT contain the phrase:
Audio format is not Red Book PCM

the lines that contain this phrase must remain intact.

Try this:

Select Search | Replace… from the main menu, fill in the dialog like this:

Find what: (?-s)^(?!.*?Audio format is not Red Book PCM).*(\R|\z)
Replace with: (leave empty)
Wrap around checked
Search Mode: Regular expression

and click Replace All.

I’m not on a PC currently but this type of question has been asked many times.

THIS is a post I presented which should help you.

Terry