previous message contains two mistakes, one (A) due to transmission, one (B) due to me.
A. 'prepare a folder somewhere' is item 0 (zero) of the procedure; 'select the message was item 1 (one); 3 and 4 where instead 2 and 3;
B. ' If you can read a message' is ' If you wish to read a message'.
(Having read the defeatist :)) answer of leocg, I decided to create the archive - for opera mail - on my own.)