Can't boot into desktop GUI

Question

I have a Model 3 B+, and I used Etcher to flash Raspian onto a 32GB SD card. I can SSH in to use the terminal, but I can't boot into the GUI.

I went into the config and adjusted the Boot Options to Desktop Autologin, and then rebooted like the system suggested.

When I reboot, Putty just says "Server unexpectedly closed network connection", the activity light on the Pi blinks for a while, I close and re-open the connection, but it just boots into the terminal again.

Below is what happens when I try to run sudo startx:

X.Org X Server 1.19.2
Release Date: 2017-03-02
X Protocol Version 11, Revision 0
Build Operating System: Linux 4.9.41-v7+ armv7l Raspbian
Current Operating System: Linux raspberrypi 4.14.79-v7+ #1159 SMP Sun Nov 4 17:50:20 GMT 2018 armv7l
Kernel command line: 8250.nr_uarts=0 bcm2708_fb.fbwidth=656 bcm2708_fb.fbheight=416 bcm2708_fb.fbswap=1 vc_mem.mem_base=0x3ec00000 vc_mem.mem_size=0x40000000  dwc_otg.lpm_enable=0 console=ttyS0,115200 console=tty1 root=PARTUUID=1a56d02d-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consoles
Build Date: 18 October 2017  04:55:30PM
xorg-server 2:1.19.2-1+rpt1+deb9u2 (https://www.debian.org/support)
Current version of pixman: 0.34.0
        Before reporting problems, check http://wiki.x.org
        to make sure that you have the latest version.
Markers: (--) probed, (**) from config file, (==) default setting,
        (++) from command line, (!!) notice, (II) informational,
        (WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/Xorg.1.log", Time: Mon Jan 21 00:21:43 2019
(==) Using system config directory "/usr/share/X11/xorg.conf.d"
modprobe: FATAL: Module g2d_23 not found in directory /lib/modules/4.14.79-v7+

Answer 1

If you want to see those graphical application on Windows, you'll need to install an X server locally (e.g. Xming) and configure your PuTTY connection to perform X11 forwarding.

No idea about what the cause of the reset could be w/out more context, it could be that the real cause is unrelated to the X error you see (as suggested here).

Answer 2

when you say the GUI won't start is the Pi actually plugged into a monitor or are you just accessing it via PuTTY?

If your just accessing the Pi via PuTTY you won't see GUI as you can only access the commandline via PuTTY. For a desktop you'll need either a monitor hooked up or to connect via VNC or other remote desktop setup.

The message from PuTTY is to be expected as you're connected to the Pi and when you send a shutdown/reboot signal you will be disconnected as the Pi will switch off. As PuTTY is on the machine your using and not the Pi itself it doesn't know what you're doing on there only that all of a sudden its connection has dropped out so you'll get that pop up about the connection has stopped unexpectedly.