When suddenly encountering this error message, I saw there was a code fix of the logon.php.However, when comparing the code to what I already have, the relevant changes were already implemented, while some others were not.Of course I wanted to know my current version, but I could no longer logon, so that was not an option.I found this SQL to execute on the database: select ostversion from table ost_config, but the field wasn't there!!Then I decided to do an upgrade with 1.10.1. Trying to execute the upgrade.php it asked me to logon.So there again, I was stuck. I changed the logon.php so that I would not get the csrf error anymore.But then I got access denied. Thinking that something was the matter with my password, I changed it in the database, with the MD5 function.Still no results. I get alternating messages of "access denied" and "authentication required".So what is there left for me to do, without doing a full reinstall? I have entered many many parameters, and don't want to loose them.That would be days work to correct all the settings. There are a few customisations in the code as well, but I have a backup of those.