LouisGac wrote: Updating from 150831 to last build with comfortUpdate doesn't make any problem here.

As far as I know 150831 build means 2.06+ not 2.05. The 2.05 build isn't mentioned by the threadstarter.

yes sorry, I should have been more explicit:

Knowing that we had a bug about the notification table update few time ago, I was worried that when coming from a fresh installed release without that table, the bug was still there. That what I checked: coming from a version without this table, to the latest one. So, I did it from a very old build, to check if anything else was wrong.

If updating from 2.06 to 2.60 there is no bug in database update, there will not be either bug in 2.05 to 2.60 database update.

I bet that OP did a manual update with mistakes.