Hi,
I am not completely new to debian, I played around with it for almost a year on VMs, and started using it a lot for the last three months.
It is my first install on real hardware though.

I successfully installed debian 9 as a dual boot with windows 10.
I chose automatic partitioning of a free space of 37 gb next to the windows partition.
A swap and ext4 partition were created, efi recognized, everything was ok.
I know it is a small partition, but I checked on debian sites, and it should be more than enough to start customizing the system, and installing/setting basic applications I think.
The only thing that surprised me was the swap created was quite big; almost half the space, but I should trust that the installer knows better )

Everything went fine, grub was installed correctly.
The computer is an asus laptop, one year old, intel i7, 16gb ram, 500gb ssd.
The PC boots as expected, I get to the login where I can login with the user account as well as the root account.

The problem is that after logging in, there is nothing but the wallpaper and the cursor..

Absolutely nothing else.. No default shortcut / hotkey works, all I could notice is that ctrl + alt + f2 makes the cursor disappear.
Nothing else seems to happen whatever I try; I have to press the shutdown key to get out..

In recovery mode, at the end of what looks like a slow booting process, I am prompted for a root password for maintenance, and, given the alternative of pressing ctrl+shift+D to "continue".

At that point, entering root password logs me in a full screen terminal as root, and, only pressing 'enter' gets me to a full screen terminal like login.
There everything looks fine, all the folders I am used to see are there, I can run commands, update apt repository..

But, once in a while (I cannot reproduce every time), Ctrl+Shift+D brings me to the graphical usual login page, and logging from there starts a normal xfce session.
Within this session, everything works as expected, I can even log out and back into the session, but a restart brings me back to the options described above.

For information, windows boot is offered by Grub, and works perfectly.

Things I have tried:

I tried of course going through the install process again, I did it 4 times for the same results exactly every time. I used two different ISO images (1 downloaded today from the official site), on a cd, and, a usb once created with rufus, another time with windisk imager. The only thing I did not try yet is using a different repo source during installation..

I tried a solution I saw on various xfce threads to remove ~/.config/xfce4 , and/or, ~/.cache to no effect.
I also tried installing ldm package as it was suggested on an ubuntu forum, but no luck.
I ran

I tried with boot secure enabled, disabled, with fast boot enabled, disabled as well.

I am sorry for such a lengthy question, especially for my first post, but I am desperate, I love debian and xfce, I practiced a bunch on VMs before taking the leap and finally giving up windows, so I am disappointed ...)
I would really appreciate any help as there is very little I could find by myself related to this issue.
Thanks a lot..

Try fresh install again this time manual partitioning with about a 1GB swap at most. Now I see no mention of you having got to the screen where you get to select the tasks to install among the options there is desktop environment among others like ssh, web server. These options may only be available from the expert install option when the installer first starts as that is the only one I do so give this one a try cannot get any worse than what is happening now.

Sounds like 3d accelerated graphics is messed up, and the XFCE4 GUI is set (as is default) to try to use window compositing (a setting in Window Manager tweaks). This would not have affected your VM installs since the VM does not get to directly control the video card.

The solution quick fix is to:

1) Press ctrl-alt-F1 to switch to a text console log in

2) log in as regular user

Find the line:
Change "true" to "false".

3) use crtl-alt-F7 to return to graphical log in screen. Log in to XFCE4

This will get you to a working XFCE4 desktop, but your 3D graphics card will still not be properly supported yet.

What graphics chip does your system have? If it is AMD (formerly ATI), then the way to get 3d graphics working correctly would normally be:

1) Add "contrib non-free" to lines in /etc/apt/sources.list so it looks something like:
2) then:

That usually does the trick for getting AMD/ATI cards working properly. But in your case, the graphics chip might be too new to be entirely properly supported. Maybe.

Thanks a lot for your input, and sorry for the late reply.
You are totally right most of the problem was about the graphic card. Well, still is actually.
I have an asus zenbook ux501, the issue is well documented here, and the solution given to change acpi settings in the grub partition sloves the problem of booting reliably and consistently into the xfce session.
There is still some issues that I am trying to solve with the nvidia card, bumblebee, and this whole new world of trouble I got myself in ))
I have a few links I tried to follow with poor level of success, and I was thinking of opening a new topic more specific to nvidia drivers.
I will do so on Sunday unless someone instructs me otherwise.
Thanks again for all the help...

Yes, open a new thread specific to nVidia driver installation. It will get more attention as a new, "zero reply" post. And will have a subject line which will bring attention from people who are familiar with nVidia driver installation.

I only have older nVidia cards which work okay with the open source driver (not the official nVidia driver). You'll need advice from someone familiar with getting more modern nVidia cards up and running.

please post output of

Thanks for your help, and sorry for the delay, I started a new topic with more details about the issue I am trying to solve.
@ondoho the output you asked for can be found over there..
Thanks again.

I'm replying here instead of the other thread for now, because I don't want to kick it off the "zero reply thread" list yet:

I notice you've got two graphics chips - Intel Corporation HD Graphics 530 (rev 06) and NVIDIA Corporation GM107M [GeForce GTX 960M] (rev a2)

I think that means that your laptop has "hybrid graphics", which is more complicated to get working properly. Since you explain you've tried stuff with "vga_switcheroo", I'm guessing you're already down the right track on that.

I can't help very much on it, since I don't have any laptop with hybrid graphics.

Thank you for the info, it gives me new directions to keep looking, I could not make that deduction myself about the hybrid graphic card...

I went straight to the VGA switcheroo page on the linux kernel documentation site to try and understand what is this thing, I can only understand a little bit from a quick read, but the "Driver power control" section seems to describe my configuration, switcheroo being in charge of switching between graphic cards. Sorry for being approximative, it is a lot of new concepts for me

I cannot make sense of all that yet, but I will keep looking into this..