Hi @simgiallorosso,
I see you’ve also asked this question elsewhere on the forum. Please just ask each question once; it’ll help avoid duplicating support effort.
For help on the MyISAM issue, try searching this forum for MyISAM; you’ll find links to information on e.g. StackOverflow that’ll help you convert your database from MyISAM to InnoDB. This is actually more of a MySQL question than an OJS question, so there are good resources elsewhere.
Thanks,
Alec Smecher
Public Knowledge Project Team