b2evolution requires innoDB. http://b2evolution.net/man/system-requirements

Who is your web host ?

Why don't they support innoDB ?

It is hosted with byethost.com
Now, I'll write to them and ask about it.
But may I just delete the /install folder and consider the upgrade done? Everything seems to be working fine... at least. And weird, 'cause I chose byethost exactely because they had the most upgraded b2e I could find (by that time, I was decided about producing with b2e but didn't know how to upgrade).

As long as the upgrade option of the installer doesn't tell you it's successful, I wouldn't consider it done.

It might work for you like this until some day you enable some option you don't use now and then it will fail...

Yep, it never told m it was done, even though in System Status it looks like it is upgraded.
I did each one of the upgrades from 5 through 6 without any problem. So am I mistaken if I assume that Innodb WAS supported before - during the previous upgrades? Would the others upgrades work properly without innodb?
I mean, byethost even offer to install b2evolution by softaculous...
Anyway, they answered me saying that innodb is not supported in freehost accounts - anymore, appearantly. So I will make my backups and look for something else.
(:

Are you using their free hosting plan?
If not which one are you using?

I think previous versions of b2evolution didn't check if the tables were correctly created as innodb... until we realized this causes some problems, so now we check... but so far we do it in a "warning" mode only.

Free hosting. But in their forum, as I mentioned, they announced (in 2013) the support for innodb engine. And it is shame, I chose them only because of the b2e (eventhough I upgraded manually, they were always up-to-date, and it was pretty stable, and an amazing support. But now I did my backups and I will start looking for another free host plan which fullfills the requirements of B2e. I do believe that b2e is way beyond the 'blog' concept, and it is pretty capable of dealing with robust content website.
(:

Thanks for the kind words about b2evo. I fear I can't say the same about free hosting though.

I have never seen a free hosting plan capable of running a serious and robust website.

And when you think about it, it makes sense... Hosting requires hardware, bandwidth, electricity, cooling and people to maintain all of this. All of this costs a lot... it just cannot be free beyond luring in the customer to upsell them... (if not it means they inject ads into your website).

Yep, you're right, it is a lot of work, but right now go to premium is not possoble for me.
Anyway, by 'robust' I meant different kinds of content well organized and managed. My website hardly will have 1000 visitors in a week. (:
But I do intend to keep producing content, and one it is public I am sure some of the users of this small community will gladly support with server/domain costs.
But back to the topic: now that b2evo check the tables, how can they (and many others) still offer b2evolution (6.6.4) for free plans without support for innodb engine?
Would it work if I backup, delete b2evo and the database, install again (6.6.4 with softaculous) and import my database back again?
EDIT: would a downgrade to 6.6.3 keep working?

Thanks a lot

6.6.3 will NOT work without innoDB any better than 6.6.4, it just won't tell you there is a problem, but the problem will still be there.

innoDB is a requirement to run b2evolution since version 2 or 3 approx.