@BitPoet This is weird... I did 3 installations. The first one went OK, the second one went haywire and gave me the same error and the third one went OK again. First, I went for a fresh install. I deleted my previous test installation, including the database. Then I did this git clone https://github.com/ryancramerdesign/ProcessWire.git test Followed by git co devns to get the latest 3.x version I made a branch from devns so I would not mess up devns since I will want to pull the repository every few weeks and merge it into laplix. git co -b laplix Then, I started the installation process, following your advice. First page, I selected the site-default profile and clicked Continue The next page showed me an error: File system is not writable by this installer. Before continuing, please rename '/site-default' to '/site' So we do have to either rename site-default or copy it. It is not done by the installer. I copied it and clicked Continue. Next page showed me some errors (needing to create .htaccess, making site/access, site/confg.php and modules writable). I copied htaccess.txt to .htaccess and chmod 777 assets/ config.php modules/ I clicked to Check again and everything went green. I clicked Continue and went to the next page. I setup the database credentials, changed nothing else and clicked Continue The next page told me that everything went OK I changed the Admin Logn URL to admin Provided the user name, password and email for the superuser Didn't do anything to the cleanup list since the files and directory could not be modified by the install script. I clicked Continue The next page warned me about my site/config.php and provided me the login form. I logged in and got to the admin page with warning about install.php and file permissions in site/config.php So, the site is installed and I am happy Since that went well, I did it again following the exact same steps (I think) with the real site name (for example, site1) and even if I did everything as before for the test installation, I got the same error as before !! Because I wanted to give as much details as possible, I did it again, writing down everything I did and this time, it worked? Unless someone knows what could cause this error, I'll mark this as close since I can now work on my site. But I would really like to understand what's provoking this error. The reason being that earlier, I had started my site with 2.7.2, the master branch. Wishing to use 3.x, I switched to devns. Switching to devns, git told me I was 4 commits behind, so I did a git pull before installation. Again the error came up. This make me fear keeping up to date with the repository. I do want to keep up to date with devns (maybe not every week but certainly every few weeks). I know that I will be subject to bugs but I don't care. This project will take some time to do since it's on my free time. And I'll report the bugs if any. I just want to know if it's me making a mistake or not. A fresh install should be painless, no? In my case, I finally managed it with 7+ installations. Not so painless... Again, thank you for your input.